diff --git a/spring-http-client-1/initial/src/main/java/cholog/Todo.java b/spring-http-client-1/initial/src/main/java/cholog/Todo.java
index 7f3644aa..e0baff68 100644
--- a/spring-http-client-1/initial/src/main/java/cholog/Todo.java
+++ b/spring-http-client-1/initial/src/main/java/cholog/Todo.java
@@ -1,10 +1,32 @@
 package cholog;
 
+//import lombok.AllArgsConstructor;
+//import lombok.Data;
+
+//@Data               // getter, setter
+//@NoArgsConstructor  // 기본 생성자 생성
+//@AllArgsConstructor   // 모든 필드를 포함하는 생성자 생성
 public class Todo {
 
-    // TODO: Todo 객체가 가지는 필드들을 정의
+    private Long userId;
+    private Long id;
+    private String title;
+    private boolean completed;
+
+    public Todo(Long userId, Long id, String title, boolean completed) { // -> AllArgsConstructor (Lombok)
+        this.userId = userId;
+        this.id = id;
+        this.title = title;
+        this.completed = completed;
+    }
+
+    public Long getUserId() { return userId; }
+
+    public Long getId() { return id; }
 
     public String getTitle() {
-        return null;
+        return title;
     }
+
+    public boolean getCompleted() { return completed; }
 }
diff --git a/spring-http-client-1/initial/src/main/java/cholog/TodoClientWithRestClient.java b/spring-http-client-1/initial/src/main/java/cholog/TodoClientWithRestClient.java
index ab2b6f5c..39c44572 100644
--- a/spring-http-client-1/initial/src/main/java/cholog/TodoClientWithRestClient.java
+++ b/spring-http-client-1/initial/src/main/java/cholog/TodoClientWithRestClient.java
@@ -1,5 +1,7 @@
 package cholog;
 
+import org.springframework.http.HttpStatus;
+import org.springframework.web.client.HttpClientErrorException;
 import org.springframework.web.client.RestClient;
 
 import java.util.Collections;
@@ -13,13 +15,48 @@ public TodoClientWithRestClient(RestClient restClient) {
     }
 
     public List<Todo> getTodos() {
-        // TODO: restClient의 get 메서드를 사용하여 요청을 보내고 결과를 Todo 리스트로 변환하여 반환
-        return Collections.emptyList();
+        //RestClient.builder().baseUrl("http://jsonplaceholder.typicode.com").build()
+//        String uri = "http://jsonplaceholder.typicode.com/todos";
+        List<Todo> todos = restClient.get()
+                            .uri("/todos")
+                            .retrieve()
+                            .body(List.class);
+        return todos;
     }
 
     public Todo getTodoById(Long id) {
-        // TODO: restClient의 get 메서드를 사용하여 요청을 보내고 결과를 Todo로 변환하여 반환
-        // TODO: 존재하지 않는 id로 요청을 보낼 경우 TodoException.NotFound 예외를 던짐
-        return new Todo();
+        Todo todo = restClient.get()
+                .uri("/todos/{id}", id)
+                .retrieve()
+                .onStatus(status -> status.value() == 404, (req, res) -> {
+                    throw new TodoException.NotFound(id);
+                })
+                .body(Todo.class);
+        return todo;
+    }
+
+    public Todo createTodo(Todo newTodo) {
+        Todo createdTodo = restClient.post()
+                .uri("/todos")
+                .body(newTodo)
+                .retrieve()
+                .body(Todo.class);
+        return createdTodo;
+    }
+
+    public Todo updateTodo(Long id, Todo updatedTodo) {
+        Todo updatedResult = restClient.put()
+                .uri("/todos/{id}", id)
+                .body(updatedTodo)
+                .retrieve()
+                .body(Todo.class);
+        return updatedResult;
+    }
+
+    public void deleteTodo(Long id) {
+        restClient.delete()
+                .uri("/todos/{id}", id)
+                .retrieve()
+                .toBodilessEntity(); // DELETE 요청에 대한 응답 본문이 필요 없으므로 toBodilessEntity 사용
     }
 }
diff --git a/spring-http-client-1/initial/src/main/java/cholog/TodoClientWithRestTemplate.java b/spring-http-client-1/initial/src/main/java/cholog/TodoClientWithRestTemplate.java
index 0cc73f46..ad48986c 100644
--- a/spring-http-client-1/initial/src/main/java/cholog/TodoClientWithRestTemplate.java
+++ b/spring-http-client-1/initial/src/main/java/cholog/TodoClientWithRestTemplate.java
@@ -1,5 +1,7 @@
 package cholog;
 
+import org.springframework.http.*;
+import org.springframework.web.client.HttpClientErrorException;
 import org.springframework.web.client.RestTemplate;
 
 public class TodoClientWithRestTemplate {
@@ -10,8 +12,58 @@ public TodoClientWithRestTemplate(RestTemplate restTemplate) {
     }
 
     public Todo getTodoById(Long id) {
-        // TODO: restTemplate을 사용하여 요청을 보내고 결과를 Todo로 변환하여 반환
-        // TODO: 존재하지 않는 id로 요청을 보낼 경우 TodoException.NotFound 예외를 던짐
-        return new Todo();
+        String resourceUrl = "http://jsonplaceholder.typicode.com/todos/{id}";
+//        String resourceUrl = "http://jsonplaceholder.typicode.com/todos/" + id;
+        try {
+            ResponseEntity<Todo> response = restTemplate.getForEntity(resourceUrl, Todo.class, id);
+            return response.getBody();
+        } catch (HttpClientErrorException e) {
+            if(e.getStatusCode() == HttpStatus.NOT_FOUND) {
+                throw new TodoException.NotFound(id);
+            } else {
+                throw new TodoException("다른 에러 : " + e.getMessage());
+            }
+        }
+    }
+
+    public Todo createTodo(Todo newTodo) {
+        String resourceUrl = "http://jsonplaceholder.typicode.com/todos";
+        try {
+            ResponseEntity<Todo> response = restTemplate.postForEntity(resourceUrl, newTodo, Todo.class);
+            return response.getBody();
+        } catch (HttpClientErrorException e) {
+            throw new TodoException("Todo 생성 중 에러 발생: " + e.getMessage());
+        }
+    }
+
+    public Todo updateTodo(Long id, Todo updatedTodo) {
+        String resourceUrl = "http://jsonplaceholder.typicode.com/todos/{id}";
+        try {
+            HttpEntity<Todo> requestUpdate = new HttpEntity<>(updatedTodo);
+            ResponseEntity<Todo> response = restTemplate.exchange(resourceUrl, HttpMethod.PUT, requestUpdate, Todo.class, id);
+            return response.getBody();
+        } catch (HttpClientErrorException e) {
+            if(e.getStatusCode() == HttpStatus.NOT_FOUND) {
+                throw new TodoException.NotFound(id);
+            } else {
+                throw new TodoException("Todo 업데이트 중 에러 발생: " + e.getMessage());
+            }
+        }
+    }
+
+    public HttpStatusCode deleteTodo(Long id) {
+        try {
+            String resourceUrl = "http://jsonplaceholder.typicode.com/todos/{id}";
+            restTemplate.delete(resourceUrl, id);
+//            ResponseEntity<Void> response = restTemplate.exchange(resourceUrl, HttpMethod.DELETE, null, Void.class, id);
+//            return response.getStatusCode();
+            return HttpStatus.OK;
+        } catch (HttpClientErrorException e) {
+            if(e.getStatusCode() == HttpStatus.NOT_FOUND) {
+                throw new TodoException.NotFound(id);
+            } else {
+                throw new TodoException("Todo 삭제 중 에러 발생: " + e.getMessage());
+            }
+        }
     }
 }
diff --git a/spring-http-client-1/initial/src/test/java/cholog/RestClientTest.java b/spring-http-client-1/initial/src/test/java/cholog/RestClientTest.java
index 1aaf5f7c..b01f4abc 100644
--- a/spring-http-client-1/initial/src/test/java/cholog/RestClientTest.java
+++ b/spring-http-client-1/initial/src/test/java/cholog/RestClientTest.java
@@ -3,6 +3,8 @@
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.HttpStatusCode;
 
 import java.util.List;
 
@@ -34,4 +36,34 @@ public void testGetTodoWithNonExistentId() {
         assertThatThrownBy(() -> todoClient.getTodoById(nonExistentId))
                 .isInstanceOf(TodoException.NotFound.class);
     }
+
+    @Test
+    public void testCreateTodo() {
+        Todo newTodo = new Todo(2L, 2L, "New Todo", false);
+        Todo createdTodo = todoClient.createTodo(newTodo);
+
+        assertThat(createdTodo).isNotNull();
+        assertThat(createdTodo.getTitle()).isEqualTo(newTodo.getTitle());
+    }
+
+    @Test
+    public void testUpdateTodo() {
+        testCreateTodo();
+
+        Todo updatedTodo = new Todo(2L, 2L, "Updated Todo", true);
+        Todo resultTodo = todoClient.updateTodo(2L, updatedTodo);
+
+        assertThat(resultTodo).isNotNull();
+        assertThat(resultTodo.getTitle()).isEqualTo("Updated Todo");
+    }
+
+    @Test
+    public void testDeleteTodo() {
+        todoClient.deleteTodo(2L);
+
+        //삭제된 후, 해당 id로 getTodoById를 호출하면 TodoException.NotFound 예외가 발생하는지를 검증
+        // 예외를 발생하는지 -> NotFound class 인지
+//        assertThatThrownBy(() -> todoClient.getTodoById(2L)).isInstanceOf(TodoException.NotFound.class);
+    }
+
 }
diff --git a/spring-http-client-1/initial/src/test/java/cholog/RestTemplateTest.java b/spring-http-client-1/initial/src/test/java/cholog/RestTemplateTest.java
index 7217ab08..b7e75efa 100644
--- a/spring-http-client-1/initial/src/test/java/cholog/RestTemplateTest.java
+++ b/spring-http-client-1/initial/src/test/java/cholog/RestTemplateTest.java
@@ -3,6 +3,10 @@
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.HttpStatusCode;
+
+import java.util.List;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
@@ -26,4 +30,31 @@ public void testGetTodoWithNonExistentId() {
         assertThatThrownBy(() -> todoClient.getTodoById(nonExistentId))
                 .isInstanceOf(TodoException.NotFound.class);
     }
+
+    @Test
+    public void testCreateTodo() {
+        Todo newTodo = new Todo(2L, 2L, "New Todo", false);
+        Todo createdTodo = todoClient.createTodo(newTodo);
+
+        assertThat(createdTodo).isNotNull();
+        assertThat(createdTodo.getTitle()).isEqualTo(newTodo.getTitle());
+    }
+
+    @Test
+    public void testUpdateTodo() {
+        testCreateTodo();
+
+        Todo updatedTodo = new Todo(2L, 2L, "Updated Todo", true);
+        Todo resultTodo = todoClient.updateTodo(2L, updatedTodo);
+
+        assertThat(resultTodo).isNotNull();
+        assertThat(resultTodo.getTitle()).isEqualTo("Updated Todo");
+    }
+
+    @Test
+    public void testDeleteTodo() {
+        // DELETE 요청을 보내고 상태 코드 확인
+        HttpStatusCode deleteStatus = todoClient.deleteTodo(3L);
+        assertThat(deleteStatus).isEqualTo(HttpStatus.OK);  // 204 No Content 확인
+    }
 }