diff --git a/assets/locales/en.toml b/assets/locales/en.toml
new file mode 100644
index 0000000..6b66b21
--- /dev/null
+++ b/assets/locales/en.toml
@@ -0,0 +1,52 @@
+# English translations for Ropy
+
+# Application
+app_name = "Ropy"
+app_description = "A clipboard manager built with Rust and GPUI"
+
+# Tray menu
+tray_show = "Show"
+tray_quit = "Quit"
+
+# Main window
+search_placeholder = "Use / to search ... "
+no_records = "No clipboard records"
+clear_all = "Clear All"
+pin = "Pin"
+unpin = "Unpin"
+
+# Settings
+settings_title = "Ropy Settings"
+settings_back = "←"
+settings_cancel = "Cancel"
+settings_save = "Save"
+
+# Settings sections
+settings_language = "Language"
+settings_language_description = "Select your preferred language"
+
+settings_theme = "Theme"
+settings_theme_light = "Light"
+settings_theme_dark = "Dark"
+settings_theme_system = "System"
+
+settings_hotkey = "Hotkey Configuration"
+settings_activation_key = "Activation Key"
+
+settings_storage = "Storage Configuration"
+settings_max_history = "Max History Records"
+
+settings_system = "System"
+settings_autostart = "Launch at system startup"
+settings_autostart_on = "ON"
+settings_autostart_off = "OFF"
+
+# Content types
+content_type_text = "Text"
+content_type_image = "Image"
+content_type_file = "File"
+
+# Messages
+message_copied = "Copied to clipboard"
+message_deleted = "Record deleted"
+message_cleared = "History cleared"
diff --git a/assets/locales/zh-CN.toml b/assets/locales/zh-CN.toml
new file mode 100644
index 0000000..4951035
--- /dev/null
+++ b/assets/locales/zh-CN.toml
@@ -0,0 +1,52 @@
+# 简体中文翻译
+
+# 应用程序
+app_name = "Ropy"
+app_description = "基于 Rust 和 GPUI 构建的剪贴板管理器"
+
+# 托盘菜单
+tray_show = "显示"
+tray_quit = "退出"
+
+# 主窗口
+search_placeholder = "使用 / 搜索 ... "
+no_records = "无剪贴板记录"
+clear_all = "清空全部"
+pin = "固定"
+unpin = "取消固定"
+
+# 设置
+settings_title = "Ropy 设置"
+settings_back = "←"
+settings_cancel = "取消"
+settings_save = "保存"
+
+# 设置选项
+settings_language = "语言"
+settings_language_description = "选择您偏好的语言"
+
+settings_theme = "主题"
+settings_theme_light = "浅色"
+settings_theme_dark = "深色"
+settings_theme_system = "跟随系统"
+
+settings_hotkey = "快捷键配置"
+settings_activation_key = "激活快捷键"
+
+settings_storage = "存储配置"
+settings_max_history = "最大历史记录数"
+
+settings_system = "系统"
+settings_autostart = "开机自动启动"
+settings_autostart_on = "开启"
+settings_autostart_off = "关闭"
+
+# 内容类型
+content_type_text = "文本"
+content_type_image = "图片"
+content_type_file = "文件"
+
+# 消息
+message_copied = "已复制到剪贴板"
+message_deleted = "记录已删除"
+message_cleared = "历史已清空"
diff --git a/doc/Multi-Language.md b/doc/Multi-Language.md
new file mode 100644
index 0000000..92f1fad
--- /dev/null
+++ b/doc/Multi-Language.md
@@ -0,0 +1,50 @@
+# Multi-Language Support
+
+Ropy now supports multiple languages! Users can easily switch between different languages through the settings panel.
+
+## Supported Languages
+
+- **English** (en)
+- **简体中文** (Simplified Chinese, zh-CN)
+
+## How to Use
+
+1. Open Ropy application
+2. Click the **Settings** button (gear icon) in the top right corner
+3. In the Settings panel, find the **Language** section
+4. Click on your preferred language button
+5. Click **Save** to apply the changes
+6. The UI will immediately switch to the selected language
+
+## Adding New Languages
+
+To add a new language:
+
+1. Create a new TOML file in `assets/locales/` directory (e.g., `fr.toml` for French)
+2. Copy the structure from `en.toml` and translate all strings
+3. Update `src/i18n/mod.rs`:
+   - Add a new variant to the `Language` enum
+   - Update the `code()`, `display_name()`, and `all()` methods
+   - Add the new language to the `load_language()` match statement
+4. Recompile the application
+
+## Translation File Format
+
+Translation files use TOML format with simple key-value pairs:
+
+```toml
+# Application
+app_name = "Ropy"
+app_description = "A clipboard manager built with Rust and GPUI"
+
+# Tray menu
+tray_show = "Show"
+tray_quit = "Quit"
+```
+
+## Implementation Details
+
+- Translations are embedded into the binary at compile time using `include_str!()` for optimal performance
+- The i18n system is lightweight and has minimal runtime overhead
+- Language selection is persisted in the user's configuration file
+- All UI strings are centralized in locale files for easy maintenance
diff --git a/doc/TODO.md b/doc/TODO.md
index b95ab54..8006aa5 100644
--- a/doc/TODO.md
+++ b/doc/TODO.md
@@ -1,7 +1,6 @@
 # TODO
 
 - Import and export clipboard history
-- Support for multiple languages
 - Support for html content type
 - Log files
 - Provide installation packages and distribution channels
diff --git a/src/config/settings.rs b/src/config/settings.rs
index 6450f73..eae2095 100644
--- a/src/config/settings.rs
+++ b/src/config/settings.rs
@@ -1,3 +1,4 @@
+use crate::i18n::Language;
 use config::{Config, ConfigError, File};
 use serde::{Deserialize, Serialize};
 use std::path::PathBuf;
@@ -13,6 +14,8 @@ pub struct Settings {
     pub theme: AppTheme,
     /// Auto-start configuration
     pub autostart: AutoStartSettings,
+    /// Language configuration
+    pub language: Language,
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
@@ -67,6 +70,7 @@ impl Default for Settings {
             },
             theme: AppTheme::System,
             autostart: AutoStartSettings { enabled: false },
+            language: Language::default(),
         }
     }
 }
diff --git a/src/gui/app.rs b/src/gui/app.rs
index 834f1d1..e9242ac 100644
--- a/src/gui/app.rs
+++ b/src/gui/app.rs
@@ -225,7 +225,7 @@ pub fn launch_app() {
             copy_tx,
         );
         setup_hotkey_listener(window_handle, async_app.clone());
-        start_tray_handler(window_handle, async_app.clone());
+        start_tray_handler(window_handle, async_app.clone(), settings.clone());
 
         cx.activate(true);
     });
diff --git a/src/gui/board/mod.rs b/src/gui/board/mod.rs
index d03c6c8..ad88a41 100644
--- a/src/gui/board/mod.rs
+++ b/src/gui/board/mod.rs
@@ -5,6 +5,7 @@ mod settings;
 use crate::clipboard::LastCopyState;
 use crate::config::Settings;
 use crate::gui::hide_window;
+use crate::i18n::{I18n, Language};
 use crate::repository::models::ContentType;
 use crate::repository::{ClipboardRecord, ClipboardRepository};
 use gpui::{
@@ -41,6 +42,9 @@ pub struct RopyBoard {
     selected_theme: usize, // 0: Light, 1: Dark, 2: System
     autostart_enabled: bool,
     pinned: bool,
+    // I18n
+    i18n: I18n,
+    selected_language: usize, // Index into Language::all()
 }
 
 impl RopyBoard {
@@ -69,7 +73,7 @@ impl RopyBoard {
             cx.new(|cx| InputState::new(window, cx).placeholder("Use / to search ... "));
         let list_state = ListState::new(0, ListAlignment::Top, gpui::px(100.));
 
-        let (max_history_records, activation_key, theme_index) = {
+        let (max_history_records, activation_key, theme_index, language) = {
             let settings_guard = settings.read().unwrap();
             let theme_idx = match settings_guard.theme {
                 crate::config::AppTheme::Light => 0,
@@ -80,6 +84,7 @@ impl RopyBoard {
                 settings_guard.storage.max_history_records,
                 settings_guard.hotkey.activation_key.clone(),
                 theme_idx,
+                settings_guard.language,
             )
         };
         let autostart_enabled = settings.read().unwrap().autostart.enabled;
@@ -87,6 +92,13 @@ impl RopyBoard {
             cx.new(|cx| InputState::new(window, cx).placeholder(activation_key.to_string()));
         let settings_max_history_input =
             cx.new(|cx| InputState::new(window, cx).placeholder(max_history_records.to_string()));
+        
+        // Initialize I18n with the language from settings
+        let i18n = I18n::new(language).unwrap_or_default();
+        let selected_language = Language::all()
+            .iter()
+            .position(|&lang| lang == language)
+            .unwrap_or(0);
 
         Self {
             records,
@@ -106,6 +118,8 @@ impl RopyBoard {
             selected_theme: theme_index,
             autostart_enabled,
             pinned: false,
+            i18n,
+            selected_language,
         }
     }
 
@@ -212,17 +226,30 @@ impl RopyBoard {
             _ => crate::config::AppTheme::System,
         };
 
+        let language = Language::all().get(self.selected_language).copied().unwrap_or_default();
+
         {
             let mut settings = self.settings.write().unwrap();
             settings.hotkey.activation_key = activation_key.clone();
             settings.storage.max_history_records = max_history;
             settings.theme = theme.clone();
             settings.autostart.enabled = self.autostart_enabled;
+            settings.language = language;
             if let Err(e) = settings.save() {
                 eprintln!("[ropy] Failed to save settings: {e}");
             }
         }
 
+        // Apply the new language
+        if let Err(e) = self.i18n.set_language(language) {
+            eprintln!("[ropy] Failed to set language: {e}");
+        }
+
+        // Update search placeholder with new language
+        self.search_input.update(cx, |input, cx| {
+            input.set_placeholder(self.i18n.t("search_placeholder"), window, cx);
+        });
+
         // Sync auto-start state with system
         if let Err(e) = self.sync_autostart_state() {
             eprintln!("[ropy] Failed to sync auto-start state: {e}");
@@ -291,7 +318,7 @@ impl Render for RopyBoard {
             .on_action(cx.listener(Self::on_select_next))
             .on_action(cx.listener(Self::on_confirm_selection))
             .on_key_down(cx.listener(Self::on_key_down))
-            .child(render_header(self.pinned, cx))
+            .child(render_header(self, cx))
             .child(render_search_input(&self.search_input, cx))
             .child(self.render_records_list(cx))
     }
diff --git a/src/gui/board/render.rs b/src/gui/board/render.rs
index e9c8e20..161461e 100644
--- a/src/gui/board/render.rs
+++ b/src/gui/board/render.rs
@@ -40,11 +40,11 @@ fn get_hex_color(content: &str) -> Option<gpui::Rgba> {
 }
 
 /// Create the "Clear" button element
-pub(super) fn create_clear_button(cx: &mut Context<'_, RopyBoard>) -> impl IntoElement {
+pub(super) fn create_clear_button(board: &RopyBoard, cx: &mut Context<'_, RopyBoard>) -> impl IntoElement {
     Button::new("clear-button")
         .ghost()
         .icon(Icon::empty().path("clear-all.svg"))
-        .tooltip("Clear All")
+        .tooltip(board.i18n.t("clear_all"))
         .on_click(cx.listener(|this, _, _, _| {
             this.clear_history();
             this.clear_last_copy_state();
@@ -65,8 +65,13 @@ pub(super) fn format_clipboard_content(record: &ClipboardRecord) -> String {
 }
 
 /// Render the header section with title and settings/clear buttons
-pub fn render_header(pinned: bool, cx: &mut Context<'_, RopyBoard>) -> impl IntoElement {
-    let is_pinned = pinned;
+pub fn render_header(board: &RopyBoard, cx: &mut Context<'_, RopyBoard>) -> impl IntoElement {
+    let is_pinned = board.pinned;
+    let pin_tooltip = if is_pinned {
+        board.i18n.t("unpin")
+    } else {
+        board.i18n.t("pin")
+    };
     let header = h_flex().justify_between().items_center().mb_4().pt_4();
 
     #[cfg(target_os = "windows")]
@@ -80,7 +85,7 @@ pub fn render_header(pinned: bool, cx: &mut Context<'_, RopyBoard>) -> impl Into
                 .text_lg()
                 .text_color(cx.theme().foreground)
                 .font_weight(gpui::FontWeight::BOLD)
-                .child("Ropy"),
+                .child(board.i18n.t("app_name")),
         )
         .child(
             h_flex()
@@ -93,7 +98,7 @@ pub fn render_header(pinned: bool, cx: &mut Context<'_, RopyBoard>) -> impl Into
                         Button::new("pin-button").ghost()
                     }
                     .icon(Icon::empty().path("pin-to-top.svg"))
-                    .tooltip("Pin to top")
+                    .tooltip(pin_tooltip)
                     .on_click(cx.listener(|this, _, window, cx| {
                         this.pinned = !this.pinned;
                         set_always_on_top(window, cx, this.pinned);
@@ -116,7 +121,7 @@ pub fn render_header(pinned: bool, cx: &mut Context<'_, RopyBoard>) -> impl Into
                         }))
                         .on_mouse_down(gpui::MouseButton::Left, |_, _, cx| cx.stop_propagation()),
                 )
-                .child(create_clear_button(cx)),
+                .child(create_clear_button(board, cx)),
         )
 }
 
diff --git a/src/gui/board/settings.rs b/src/gui/board/settings.rs
index 1f12476..21bb61e 100644
--- a/src/gui/board/settings.rs
+++ b/src/gui/board/settings.rs
@@ -1,3 +1,4 @@
+use crate::i18n::{I18n, Language};
 use gpui::{
     Context, div,
     prelude::{InteractiveElement, IntoElement, ParentElement, Styled},
@@ -11,20 +12,59 @@ use super::RopyBoard;
 #[cfg(target_os = "windows")]
 use crate::gui::utils::start_window_drag;
 
+/// Render language selection buttons
+/// Note: Uses index-based selection from Language::all() which maintains a stable order.
+/// The order is: English, ChineseSimplified
+fn render_language_selector(board: &mut RopyBoard, cx: &mut Context<RopyBoard>) -> impl IntoElement {
+    let languages = Language::all();
+
+    h_flex()
+        .gap_2()
+        .items_center()
+        .children(languages.iter().enumerate().map(|(index, lang)| {
+            let is_selected = board.selected_language == index;
+            let lang_copy = *lang; // Copy the language for the closure
+
+            let mut button = Button::new(("language-button", index))
+                .small()
+                .label(lang.display_name());
+
+            button = if is_selected {
+                button.primary()
+            } else {
+                button.ghost()
+            };
+
+            button.on_click(cx.listener(move |board, _, window, cx| {
+                board.selected_language = index;
+                // Update search placeholder immediately for instant feedback
+                if let Ok(temp_i18n) = I18n::new(lang_copy) {
+                    board.search_input.update(cx, |input, cx| {
+                        input.set_placeholder(temp_i18n.t("search_placeholder"), window, cx);
+                    });
+                }
+                cx.notify();
+            }))
+        }))
+}
+
 /// Render theme selection buttons
 fn render_theme_selector(board: &mut RopyBoard, cx: &mut Context<RopyBoard>) -> impl IntoElement {
-    let themes = [("Light", 0), ("Dark", 1), ("System", 2)];
+    let theme_names = vec![
+        board.i18n.t("settings_theme_light"),
+        board.i18n.t("settings_theme_dark"),
+        board.i18n.t("settings_theme_system"),
+    ];
 
     h_flex()
         .gap_2()
         .items_center()
-        .children(themes.iter().map(|(name, index)| {
-            let is_selected = board.selected_theme == *index;
-            let index_val = *index;
+        .children(theme_names.into_iter().enumerate().map(|(index, name)| {
+            let is_selected = board.selected_theme == index;
 
-            let mut button = Button::new(("theme-button", index_val))
+            let mut button = Button::new(("theme-button", index))
                 .small()
-                .label(*name);
+                .label(name);
 
             button = if is_selected {
                 button.primary()
@@ -33,7 +73,7 @@ fn render_theme_selector(board: &mut RopyBoard, cx: &mut Context<RopyBoard>) ->
             };
 
             button.on_click(cx.listener(move |board, _, _window, cx| {
-                board.selected_theme = index_val;
+                board.selected_theme = index;
                 cx.notify();
             }))
         }))
@@ -52,7 +92,7 @@ pub(super) fn render_settings_content(
             Button::new("cancel-button")
                 .small()
                 .ghost()
-                .label("Cancel")
+                .label(board.i18n.t("settings_cancel"))
                 .on_click(cx.listener(|board, _, window, cx| {
                     // Clear input fields
                     board.settings_max_history_input.update(cx, |input, cx| {
@@ -70,7 +110,7 @@ pub(super) fn render_settings_content(
         .child(
             Button::new("save-button")
                 .small()
-                .label("Save")
+                .label(board.i18n.t("settings_save"))
                 .on_click(cx.listener(|board, _, window, cx| {
                     board.save_settings(cx, window);
                 })),
@@ -82,7 +122,7 @@ pub(super) fn render_settings_content(
         .child(
             div()
                 .text_color(cx.theme().foreground)
-                .child("Max History Records"),
+                .child(board.i18n.t("settings_max_history")),
         )
         .child(
             Input::new(&board.settings_max_history_input)
@@ -100,7 +140,7 @@ pub(super) fn render_settings_content(
             div()
                 .text_xs()
                 .text_color(cx.theme().foreground)
-                .child("Activation Key"),
+                .child(board.i18n.t("settings_activation_key")),
         )
         .child(
             Input::new(&board.settings_activation_key_input)
@@ -119,9 +159,21 @@ pub(super) fn render_settings_content(
                 .text_sm()
                 .text_color(cx.theme().muted_foreground)
                 .font_weight(gpui::FontWeight::BOLD)
-                .child("Hotkey Configuration"),
+                .child(board.i18n.t("settings_hotkey")),
         )
         .child(activation_key_label);
+    
+    let language_section = v_flex()
+        .gap_2()
+        .child(
+            div()
+                .text_sm()
+                .text_color(cx.theme().muted_foreground)
+                .font_weight(gpui::FontWeight::BOLD)
+                .child(board.i18n.t("settings_language")),
+        )
+        .child(render_language_selector(board, cx));
+    
     let theme_section = v_flex()
         .gap_2()
         .child(
@@ -129,7 +181,7 @@ pub(super) fn render_settings_content(
                 .text_sm()
                 .text_color(cx.theme().muted_foreground)
                 .font_weight(gpui::FontWeight::BOLD)
-                .child("Theme"),
+                .child(board.i18n.t("settings_theme")),
         )
         .child(render_theme_selector(board, cx));
     let storage_section = v_flex()
@@ -139,7 +191,7 @@ pub(super) fn render_settings_content(
                 .text_sm()
                 .text_color(cx.theme().muted_foreground)
                 .font_weight(gpui::FontWeight::BOLD)
-                .child("Storage Configuration"),
+                .child(board.i18n.t("settings_storage")),
         )
         .child(max_history_input_field);
     let autostart_section = v_flex()
@@ -149,7 +201,7 @@ pub(super) fn render_settings_content(
                 .text_sm()
                 .text_color(cx.theme().muted_foreground)
                 .font_weight(gpui::FontWeight::BOLD)
-                .child("System"),
+                .child(board.i18n.t("settings_system")),
         )
         .child(
             h_flex()
@@ -158,15 +210,15 @@ pub(super) fn render_settings_content(
                 .child(
                     div()
                         .text_color(cx.theme().foreground)
-                        .child("Launch at system startup"),
+                        .child(board.i18n.t("settings_autostart")),
                 )
                 .child({
                     let mut button = Button::new("autostart-toggle").small();
 
                     button = if board.autostart_enabled {
-                        button.primary().label("ON")
+                        button.primary().label(board.i18n.t("settings_autostart_on"))
                     } else {
-                        button.ghost().label("OFF")
+                        button.ghost().label(board.i18n.t("settings_autostart_off"))
                     };
 
                     button.on_click(cx.listener(|board, _, _, cx| {
@@ -183,7 +235,7 @@ pub(super) fn render_settings_content(
             Button::new("back-button")
                 .small()
                 .ghost()
-                .label("←")
+                .label(board.i18n.t("settings_back"))
                 .on_click(cx.listener(|board, _, window, cx| {
                     board.show_settings = false;
                     window.focus(&board.focus_handle);
@@ -196,7 +248,7 @@ pub(super) fn render_settings_content(
                 .text_lg()
                 .text_color(cx.theme().foreground)
                 .font_weight(gpui::FontWeight::BOLD)
-                .child("Ropy Settings"),
+                .child(board.i18n.t("settings_title")),
         )
         .child(div().w(px(55.)));
 
@@ -212,6 +264,7 @@ pub(super) fn render_settings_content(
             v_flex()
                 .gap_4()
                 .flex_1()
+                .child(language_section)
                 .child(theme_section)
                 // .child(hotkey_section)
                 .child(storage_section)
diff --git a/src/gui/tray.rs b/src/gui/tray.rs
index ca84b0d..98c80d1 100644
--- a/src/gui/tray.rs
+++ b/src/gui/tray.rs
@@ -1,3 +1,7 @@
+use crate::config::Settings;
+use crate::i18n::I18n;
+use std::sync::RwLock;
+use std::sync::Arc;
 use std::time::Duration;
 
 use gpui::{AsyncApp, WindowHandle};
@@ -8,10 +12,13 @@ use tray_icon::{
 };
 
 /// Initialize and return the tray icon
-pub fn init_tray() -> Result<(TrayIcon, MenuId, MenuId), Box<dyn std::error::Error>> {
+pub fn init_tray(settings: Arc<RwLock<Settings>>) -> Result<(TrayIcon, MenuId, MenuId), Box<dyn std::error::Error>> {
+    let language = settings.read().unwrap().language;
+    let i18n = I18n::new(language).unwrap_or_default();
+
     // Create menu items
-    let show_item = MenuItem::new("Show", true, None);
-    let quit_item = MenuItem::new("Quit", true, None);
+    let show_item = MenuItem::new(i18n.t("tray_show"), true, None);
+    let quit_item = MenuItem::new(i18n.t("tray_quit"), true, None);
 
     // Create menu
     let tray_menu = Menu::new();
@@ -23,7 +30,7 @@ pub fn init_tray() -> Result<(TrayIcon, MenuId, MenuId), Box<dyn std::error::Err
     // Create tray icon
     let tray = TrayIconBuilder::new()
         .with_menu(Box::new(tray_menu))
-        .with_tooltip("Ropy")
+        .with_tooltip(i18n.t("app_name").as_str())
         .with_icon(icon)
         .with_menu_on_left_click(false)
         .build()?;
@@ -41,10 +48,10 @@ fn create_icon() -> Result<Icon, Box<dyn std::error::Error>> {
 }
 
 /// Start the system tray handler
-pub fn start_tray_handler(window_handle: WindowHandle<Root>, async_app: AsyncApp) {
+pub fn start_tray_handler(window_handle: WindowHandle<Root>, async_app: AsyncApp, settings: Arc<RwLock<Settings>>) {
     let fg_executor = async_app.foreground_executor().clone();
     let bg_executor = async_app.background_executor().clone();
-    match init_tray() {
+    match init_tray(settings) {
         Ok((tray, show_id, quit_id)) => {
             println!("[ropy] Tray icon initialized successfully");
             // Keep tray icon alive for the lifetime of the application
diff --git a/src/i18n/mod.rs b/src/i18n/mod.rs
new file mode 100644
index 0000000..a69a90a
--- /dev/null
+++ b/src/i18n/mod.rs
@@ -0,0 +1,200 @@
+use serde::{Deserialize, Serialize};
+use std::collections::HashMap;
+use thiserror::Error;
+
+/// Supported languages
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
+pub enum Language {
+    #[serde(rename = "en")]
+    English,
+    #[serde(rename = "zh-CN")]
+    ChineseSimplified,
+}
+
+impl Language {
+    pub fn code(&self) -> &'static str {
+        match self {
+            Language::English => "en",
+            Language::ChineseSimplified => "zh-CN",
+        }
+    }
+
+    pub fn display_name(&self) -> &'static str {
+        match self {
+            Language::English => "English",
+            Language::ChineseSimplified => "简体中文",
+        }
+    }
+
+    pub fn all() -> Vec<Language> {
+        vec![Language::English, Language::ChineseSimplified]
+    }
+}
+
+impl Default for Language {
+    fn default() -> Self {
+        Language::English
+    }
+}
+
+/// Translation keys used throughout the application
+#[derive(Debug, Clone)]
+pub struct Translations {
+    strings: HashMap<String, String>,
+}
+
+impl Translations {
+    /// Load translations from a TOML string
+    pub fn from_toml(content: &str) -> Result<Self, I18nError> {
+        let strings: HashMap<String, String> =
+            toml::from_str(content).map_err(|e| I18nError::ParseError(e.to_string()))?;
+        Ok(Self { strings })
+    }
+
+    /// Get a translated string by key
+    pub fn get(&self, key: &str) -> String {
+        self.strings
+            .get(key)
+            .cloned()
+            .unwrap_or_else(|| format!("[Missing: {}]", key))
+    }
+}
+
+/// I18n manager for handling translations
+#[derive(Debug, Clone)]
+pub struct I18n {
+    current_language: Language,
+    translations: Translations,
+}
+
+impl I18n {
+    /// Create a new I18n instance with the specified language
+    pub fn new(language: Language) -> Result<Self, I18nError> {
+        let translations = Self::load_language(language)?;
+        Ok(Self {
+            current_language: language,
+            translations,
+        })
+    }
+
+    /// Load translations for a specific language
+    fn load_language(language: Language) -> Result<Translations, I18nError> {
+        let content = match language {
+            Language::English => include_str!("../../assets/locales/en.toml"),
+            Language::ChineseSimplified => include_str!("../../assets/locales/zh-CN.toml"),
+        };
+        Translations::from_toml(content)
+    }
+
+    /// Get the current language
+    pub fn current_language(&self) -> Language {
+        self.current_language
+    }
+
+    /// Change the current language
+    pub fn set_language(&mut self, language: Language) -> Result<(), I18nError> {
+        let translations = Self::load_language(language)?;
+        self.current_language = language;
+        self.translations = translations;
+        Ok(())
+    }
+
+    /// Get a translated string by key
+    pub fn t(&self, key: &str) -> String {
+        self.translations.get(key)
+    }
+}
+
+impl Default for I18n {
+    fn default() -> Self {
+        // Try to load English as default, if that fails, create empty translations
+        match Self::new(Language::default()) {
+            Ok(i18n) => i18n,
+            Err(e) => {
+                eprintln!("[ropy] Warning: Failed to load default language translations: {e}");
+                eprintln!("[ropy] Falling back to empty translations - all strings will show as '[Missing: key]'");
+                Self {
+                    current_language: Language::default(),
+                    translations: Translations {
+                        strings: HashMap::new(),
+                    },
+                }
+            }
+        }
+    }
+}
+
+/// I18n-related errors
+#[derive(Debug, Error)]
+pub enum I18nError {
+    #[error("Failed to parse translation file: {0}")]
+    ParseError(String),
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_language_code() {
+        assert_eq!(Language::English.code(), "en");
+        assert_eq!(Language::ChineseSimplified.code(), "zh-CN");
+    }
+
+    #[test]
+    fn test_language_display_name() {
+        assert_eq!(Language::English.display_name(), "English");
+        assert_eq!(Language::ChineseSimplified.display_name(), "简体中文");
+    }
+
+    #[test]
+    fn test_translations_from_toml() {
+        let content = r#"
+            app_name = "Ropy"
+            show = "Show"
+            quit = "Quit"
+        "#;
+        let translations = Translations::from_toml(content).unwrap();
+        assert_eq!(translations.get("app_name"), "Ropy");
+        assert_eq!(translations.get("show"), "Show");
+        assert_eq!(translations.get("quit"), "Quit");
+    }
+
+    #[test]
+    fn test_missing_translation() {
+        let content = r#"
+            app_name = "Ropy"
+        "#;
+        let translations = Translations::from_toml(content).unwrap();
+        assert_eq!(translations.get("missing_key"), "[Missing: missing_key]");
+    }
+
+    #[test]
+    fn test_i18n_initialization() {
+        let i18n = I18n::new(Language::English);
+        assert!(i18n.is_ok());
+        let i18n = i18n.unwrap();
+        assert_eq!(i18n.current_language(), Language::English);
+        assert_eq!(i18n.t("app_name"), "Ropy");
+    }
+
+    #[test]
+    fn test_i18n_language_switch() {
+        let mut i18n = I18n::new(Language::English).unwrap();
+        assert_eq!(i18n.t("tray_show"), "Show");
+
+        // Switch to Chinese
+        let result = i18n.set_language(Language::ChineseSimplified);
+        assert!(result.is_ok());
+        assert_eq!(i18n.current_language(), Language::ChineseSimplified);
+        assert_eq!(i18n.t("tray_show"), "显示");
+    }
+
+    #[test]
+    fn test_language_all() {
+        let languages = Language::all();
+        assert_eq!(languages.len(), 2);
+        assert!(languages.contains(&Language::English));
+        assert!(languages.contains(&Language::ChineseSimplified));
+    }
+}
diff --git a/src/main.rs b/src/main.rs
index 8779201..df3184b 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -3,6 +3,7 @@
 mod clipboard;
 mod config;
 mod gui;
+mod i18n;
 mod repository;
 
 #[cfg(target_os = "windows")]