diff --git a/app/src/main/java/com/stable/scoi/data/local/PreferenceManager.kt b/app/src/main/java/com/stable/scoi/data/local/PreferenceManager.kt
index 89f8f20..15f0815 100644
--- a/app/src/main/java/com/stable/scoi/data/local/PreferenceManager.kt
+++ b/app/src/main/java/com/stable/scoi/data/local/PreferenceManager.kt
@@ -72,8 +72,14 @@ class PreferenceManager @Inject constructor(
 
     fun getSimplePassword(): String = prefs.getString("SIMPLE_PASSWORD", "") ?: ""
 
+    fun setJoinStatus(isJoined:Boolean){
+        prefs.edit().putBoolean("JOIN_STATUS", isJoined).apply()
+    }
+
+    fun getJoinStatus(): Boolean {
+        return prefs.getBoolean("JOIN_STATUS", false)
+    }
 
-    // 데이터 초기화
     fun clear() {
         prefs.edit().clear().apply()
     }
diff --git a/app/src/main/java/com/stable/scoi/presentation/MainActivity.kt b/app/src/main/java/com/stable/scoi/presentation/MainActivity.kt
index 1e5cc5b..6fcfe7a 100644
--- a/app/src/main/java/com/stable/scoi/presentation/MainActivity.kt
+++ b/app/src/main/java/com/stable/scoi/presentation/MainActivity.kt
@@ -8,12 +8,14 @@ import androidx.core.view.WindowInsetsControllerCompat
 import androidx.navigation.NavController
 import androidx.navigation.fragment.NavHostFragment
 import com.stable.scoi.R
+import com.stable.scoi.data.local.PreferenceManager
 import com.stable.scoi.databinding.ActivityMainBinding
 import com.stable.scoi.extension.gone
 import com.stable.scoi.extension.visible
 import com.stable.scoi.presentation.base.BaseActivity
 import dagger.hilt.android.AndroidEntryPoint
 import kotlinx.coroutines.launch
+import javax.inject.Inject
 
 @AndroidEntryPoint
 class MainActivity : BaseActivity<ActivityMainBinding, MainActivityUiState, MainActivityEvent, MainActivityViewModel>(
@@ -22,6 +24,8 @@ class MainActivity : BaseActivity<ActivityMainBinding, MainActivityUiState, Main
     override val viewModel: MainActivityViewModel by viewModels()
     private lateinit var navController: NavController
 
+    @Inject lateinit var preferenceManager: PreferenceManager
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         val controller = WindowInsetsControllerCompat(window, window.decorView)
@@ -42,7 +46,6 @@ class MainActivity : BaseActivity<ActivityMainBinding, MainActivityUiState, Main
         repeatOnStarted {
             launch {
                 viewModel.uiEvent.collect{
-                    // TODO 이벤트 처리
                 }
             }
 
diff --git a/app/src/main/java/com/stable/scoi/presentation/ui/Auth/JoinCompleteFragment.kt b/app/src/main/java/com/stable/scoi/presentation/ui/Auth/JoinCompleteFragment.kt
index 539e301..b1dad60 100644
--- a/app/src/main/java/com/stable/scoi/presentation/ui/Auth/JoinCompleteFragment.kt
+++ b/app/src/main/java/com/stable/scoi/presentation/ui/Auth/JoinCompleteFragment.kt
@@ -6,16 +6,21 @@ import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
 import androidx.fragment.app.Fragment
+import androidx.fragment.app.viewModels
 import androidx.navigation.fragment.findNavController
 import com.stable.scoi.R
+import com.stable.scoi.data.local.PreferenceManager
 import com.stable.scoi.databinding.FragmentRegCompleteBinding
 import com.stable.scoi.presentation.MainActivity
 
 class JoinCompleteFragment : Fragment() {
-
+    private val preferenceManager: PreferenceManager by lazy { PreferenceManager(requireContext()) }
     private var _binding: FragmentRegCompleteBinding? = null
     private val binding get() = _binding!!
 
+    private val viewModel: JoinViewModel by viewModels()
+
+
     override fun onCreateView(
         inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?
     ): View {
@@ -40,18 +45,14 @@ class JoinCompleteFragment : Fragment() {
         }
     }
 
-    private fun navigateToMain() {
-        val intent = Intent(requireContext(), MainActivity::class.java)
-        intent.flags = Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK
-        startActivity(intent)
-    }
 
     override fun onDestroyView() {
         super.onDestroyView()
         _binding = null
     }
     private fun navigateToPin() {
-        findNavController().navigate(R.id.action_joinCompleteFragment_to_pinFragment)
+        preferenceManager.setJoinStatus(true)
+        findNavController().navigate(R.id.action_joinCompleteFragment_to_homeFragment)
     }
 }
 
diff --git a/app/src/main/java/com/stable/scoi/presentation/ui/Auth/JoinViewModel.kt b/app/src/main/java/com/stable/scoi/presentation/ui/Auth/JoinViewModel.kt
index d0dee25..1d22b90 100644
--- a/app/src/main/java/com/stable/scoi/presentation/ui/Auth/JoinViewModel.kt
+++ b/app/src/main/java/com/stable/scoi/presentation/ui/Auth/JoinViewModel.kt
@@ -46,6 +46,7 @@ class JoinViewModel @Inject constructor(
         viewModelScope.launch {
             authRepository.sendSms(phone)
                 .onSuccess { response ->
+                    SLOG.D("전송 성공!")
                     val remainingSeconds = calculateRemainingSeconds(response.expiredAt)
                     startTimer(remainingSeconds)
 
@@ -53,6 +54,7 @@ class JoinViewModel @Inject constructor(
                     emitEvent(JoinEvent.ShowError("인증번호가 발송되었습니다."))
                 }
                 .onFailure { e ->
+                    SLOG.D("전송 실패함 ㅋ")
                     emitEvent(JoinEvent.ShowError(e.message ?: "전송 실패"))
                 }
         }
@@ -145,50 +147,50 @@ class JoinViewModel @Inject constructor(
         }
     }
 
-//    fun submitSignUp(exchange: String, apiKey: String, secretKey: String) {
-//        val currentState = uiState.value
-//        updateState { copy(isLoading = true) }
-//
-//        viewModelScope.launch {
-//            try {
-//                val encryptedSecretKey = EncryptionUtil.encrypt(secretKey)
-//                val encryptedSimplePassword = EncryptionUtil.encrypt(currentState.simplePassword)
-//
-//                SLOG.D(encryptedSimplePassword.toString())
-//
-//                val newApiKey = ApiKeyInfo(
-//                    exchangeType = exchange,
-//                    publicKey = apiKey,
-//                    secretKey = encryptedSecretKey
-//                )
-//
-//                val request = SignUpRequest(
-//                    koreanName = currentState.koreanName,
-//                    englishName = currentState.englishName,
-//                    residentNumber = currentState.residentNumber,
-//                    phoneNumber = currentState.phoneNumber,
-//                    simplePassword = encryptedSimplePassword,
-//                    apiKeys = listOf(newApiKey),
-//                    memberType = "INDIVIDUAL",
-//                    isBioRegistered = currentState.isBioRegistered,
-//                    verificationToken = currentState.verificationToken
-//                )
-//
-//                authRepository.signUp(request)
-//                    .onSuccess {
-//                        preferenceManager.saveSimplePassword(currentState.simplePassword)
-//                        emitEvent(JoinEvent.NavigateToRegDone)
-//                    }
-//                    .onFailure { e ->
-//                        android.util.Log.e("JOIN_DEBUG", "회원가입 실패: ${e.message}")
-//                        emitEvent(JoinEvent.ShowError(e.message ?: "회원가입 실패"))
-//                    }
-//            } catch (e: Exception) {
-//                android.util.Log.e("JOIN_DEBUG", "암호화 중 오류 발생: ${e.message}")
-//                emitEvent(JoinEvent.ShowError("보안 처리 중 오류가 발생했습니다."))
-//            } finally {
-//                updateState { copy(isLoading = false) }
-//            }
-//        }
-//    }
+    fun submitSignUp(exchange: String, apiKey: String, secretKey: String) {
+        val currentState = uiState.value
+        updateState { copy(isLoading = true) }
+
+        viewModelScope.launch {
+            try {
+                val encryptedSecretKey = EncryptionUtil.encrypt(secretKey)
+                val encryptedSimplePassword = EncryptionUtil.encrypt(currentState.simplePassword)
+
+                SLOG.D(encryptedSimplePassword.toString())
+
+                val newApiKey = ApiKeyInfo(
+                    exchangeType = exchange,
+                    publicKey = apiKey,
+                    secretKey = encryptedSecretKey
+                )
+
+                val request = SignUpRequest(
+                    koreanName = currentState.koreanName,
+                    englishName = currentState.englishName,
+                    residentNumber = currentState.residentNumber,
+                    phoneNumber = currentState.phoneNumber,
+                    simplePassword = encryptedSimplePassword,
+                    apiKeys = listOf(newApiKey),
+                    memberType = "INDIVIDUAL",
+                    isBioRegistered = currentState.isBioRegistered,
+                    verificationToken = currentState.verificationToken
+                )
+
+                authRepository.signUp(request)
+                    .onSuccess {
+                        preferenceManager.saveSimplePassword(currentState.simplePassword)
+                        emitEvent(JoinEvent.NavigateToRegDone)
+                    }
+                    .onFailure { e ->
+                        android.util.Log.e("JOIN_DEBUG", "회원가입 실패: ${e.message}")
+                        emitEvent(JoinEvent.ShowError(e.message ?: "회원가입 실패"))
+                    }
+            } catch (e: Exception) {
+                android.util.Log.e("JOIN_DEBUG", "암호화 중 오류 발생: ${e.message}")
+                emitEvent(JoinEvent.ShowError("보안 처리 중 오류가 발생했습니다."))
+            } finally {
+                updateState { copy(isLoading = false) }
+            }
+        }
+    }
 }
diff --git a/app/src/main/java/com/stable/scoi/presentation/ui/Auth/KeyFragment.kt b/app/src/main/java/com/stable/scoi/presentation/ui/Auth/KeyFragment.kt
index 76e93d7..7520d59 100644
--- a/app/src/main/java/com/stable/scoi/presentation/ui/Auth/KeyFragment.kt
+++ b/app/src/main/java/com/stable/scoi/presentation/ui/Auth/KeyFragment.kt
@@ -78,8 +78,8 @@ class KeyFragment : BaseFragment<FragmentKeyBinding, JoinState, JoinEvent, JoinV
                 "업비트" -> "UPBIT"
                 else -> ""
             }
-//            viewModel.submitSignUp(exchangeType, binding.apiKeyInputEt.text.toString(), binding.secretKeyInputEt.text.toString())
-            findNavController().navigate(R.id.action_KeyFragment_to_homeFragment)
+            viewModel.submitSignUp(exchangeType, binding.apiKeyInputEt.text.toString(), binding.secretKeyInputEt.text.toString())
+            findNavController().navigate(R.id.action_KeyFragment_to_joinCompleteFragment)
         }
     }
 
diff --git a/app/src/main/java/com/stable/scoi/presentation/ui/login/LoginFragment.kt b/app/src/main/java/com/stable/scoi/presentation/ui/login/LoginFragment.kt
index d956ac9..9f676e1 100644
--- a/app/src/main/java/com/stable/scoi/presentation/ui/login/LoginFragment.kt
+++ b/app/src/main/java/com/stable/scoi/presentation/ui/login/LoginFragment.kt
@@ -4,6 +4,7 @@ import android.text.method.PasswordTransformationMethod
 import android.view.View
 import android.view.WindowManager
 import android.widget.EditText
+import androidx.core.content.ContextCompat
 import androidx.core.view.WindowInsetsCompat
 import androidx.core.view.WindowInsetsControllerCompat
 import androidx.core.widget.doOnTextChanged
@@ -38,6 +39,8 @@ class LoginFragment : BaseFragment<FragmentLoginPinBinding, LoginState, LoginEve
             binding.loginPin1Et, binding.loginPin2Et, binding.loginPin3Et,
             binding.loginPin4Et, binding.loginPin5Et, binding.loginPin6Et
         )
+        val white = ContextCompat.getColor(requireActivity(), R.color.white)
+        requireActivity().findViewById<View>(R.id.main).setBackgroundColor(white)
 
 //        pinEditTexts.forEach { editText ->
 //            editText.setOnFocusChangeListener { _, hasFocus ->
diff --git a/app/src/main/java/com/stable/scoi/presentation/ui/login/LoginViewModel.kt b/app/src/main/java/com/stable/scoi/presentation/ui/login/LoginViewModel.kt
index b9c73a1..b4b981d 100644
--- a/app/src/main/java/com/stable/scoi/presentation/ui/login/LoginViewModel.kt
+++ b/app/src/main/java/com/stable/scoi/presentation/ui/login/LoginViewModel.kt
@@ -47,7 +47,7 @@ class LoginViewModel @Inject constructor(
             updateState { this.copy(isLoading = true) }
 
             val savedPhoneNumber = preferenceManager.getPhoneNumber()
-            val currentToken = preferenceManager.getVerificationToken()
+            val currentToken = preferenceManager.getVerificationToken() // 원래는 null 값으로 되게끔 한다.
 
             if (savedPhoneNumber.isEmpty()) {
                 updateState { this.copy(isLoading = false) }
diff --git a/app/src/main/java/com/stable/scoi/presentation/ui/splash/SplashFragment.kt b/app/src/main/java/com/stable/scoi/presentation/ui/splash/SplashFragment.kt
index 15dcf28..9cc18db 100644
--- a/app/src/main/java/com/stable/scoi/presentation/ui/splash/SplashFragment.kt
+++ b/app/src/main/java/com/stable/scoi/presentation/ui/splash/SplashFragment.kt
@@ -9,6 +9,7 @@ import com.stable.scoi.presentation.base.BaseFragment
 import dagger.hilt.android.AndroidEntryPoint
 import kotlinx.coroutines.launch
 import com.stable.scoi.R
+import com.stable.scoi.data.local.PreferenceManager
 import com.stable.scoi.databinding.FragmentSplashBinding
 import com.stable.scoi.util.SLOG
 
@@ -16,8 +17,10 @@ import com.stable.scoi.util.SLOG
 class SplashFragment : BaseFragment<FragmentSplashBinding, SplashUiState, SplashUiEvent, SplashViewModel>(
     FragmentSplashBinding::inflate,
 ) {
+    private val preferenceManager: PreferenceManager by lazy { PreferenceManager(requireContext()) }
     override val viewModel: SplashViewModel by viewModels()
 
+
     override fun initView() {
         binding.apply {
             requireActivity().findViewById<View>(R.id.main).setBackgroundColor(ContextCompat.getColor(requireActivity(), R.color.active))
@@ -30,9 +33,14 @@ class SplashFragment : BaseFragment<FragmentSplashBinding, SplashUiState, Splash
 
                 override fun onAnimationEnd(animation: Animator) {
                     SLOG.D("하이?")
-                   findNavController().navigate(R.id.action_splash_fragment_to_join_auth_fragment)
-//                    findNavController().navigate(R.id.action_splash_fragment_to_loginFragment)
-                   // findNavController().navigate(R.id.action_splash_fragment_to_joinFragment)
+                    val isRegistered=preferenceManager.getJoinStatus()
+
+                    if(isRegistered==true){
+                        navigateToLogin()
+                    }
+                    else{
+                        navigateToJoinAuth()
+                    }
                 }
 
                 override fun onAnimationRepeat(animation: Animator) {
@@ -73,4 +81,10 @@ class SplashFragment : BaseFragment<FragmentSplashBinding, SplashUiState, Splash
     private fun navigateToHome() {
         findNavController().navigate(R.id.homeFragment)
     }
+    private fun navigateToLogin(){
+        findNavController().navigate(R.id.action_splashFragment_to_loginFragment)
+    }
+    private fun navigateToJoinAuth(){
+        findNavController().navigate(R.id.action_splash_fragment_to_join_auth_fragment)
+    }
 }
\ No newline at end of file
diff --git a/app/src/main/res/navigation-v26/main_graph.xml b/app/src/main/res/navigation-v26/main_graph.xml
index 585932f..ad0c51a 100644
--- a/app/src/main/res/navigation-v26/main_graph.xml
+++ b/app/src/main/res/navigation-v26/main_graph.xml
@@ -20,7 +20,7 @@
             android:id="@+id/action_splash_fragment_to_join_auth_fragment"
             app:destination="@id/joinAuthFragment"/>
         <action
-            android:id="@+id/action_splash_fragment_to_loginFragment"
+            android:id="@+id/action_splashFragment_to_loginFragment"
             app:destination="@id/login_pin_fragment"/>
     </fragment>
 
@@ -258,9 +258,6 @@
         android:id="@+id/join_fragment"
         android:name="com.stable.scoi.presentation.ui.Auth.JoinFragment"
         tools:layout="@layout/fragment_join">
-        <action
-            android:id="@+id/action_joinFragment_to_joinAuthFragment"
-            app:destination="@id/joinAuthFragment" />
         <action
             android:id="@+id/action_joinFragment_to_loginRegFragment"
             app:destination="@id/login_reg_fragment" />
@@ -319,9 +316,6 @@
         <action
             android:id="@+id/action_loginFragment_to_re_join_fragment"
             app:destination="@id/re_join_auth_fragment"/>
-        <action
-            android:id="@+id/action_loginFragment_to_bioFragment"
-            app:destination="@id/bio_fragment"/>
     </fragment>
 
     <fragment
@@ -491,6 +485,10 @@
         <action
             android:id="@+id/action_joinCompleteFragment_to_pinFragment"
             app:destination="@id/login_pin_fragment" />
+        <action
+            android:id="@+id/action_joinCompleteFragment_to_homeFragment"
+            app:destination="@id/homeFragment"
+            />
     </fragment>
 
     <fragment
@@ -536,6 +534,7 @@
             app:destination="@id/login_pin_fragment" />
     </fragment>
 
+
     <fragment
         android:id="@+id/charge_pw_fragment"
         android:name="com.stable.scoi.presentation.ui.charge.chart.ChargePwFragment"
@@ -546,7 +545,4 @@
             app:destination="@id/chargeCompleteFragment"/>
     </fragment>
 
-
-
-
-</navigation>
+</navigation>
\ No newline at end of file
diff --git a/app/src/main/res/navigation/main_graph.xml b/app/src/main/res/navigation/main_graph.xml
index dfcb4d0..ad0c51a 100644
--- a/app/src/main/res/navigation/main_graph.xml
+++ b/app/src/main/res/navigation/main_graph.xml
@@ -20,7 +20,7 @@
             android:id="@+id/action_splash_fragment_to_join_auth_fragment"
             app:destination="@id/joinAuthFragment"/>
         <action
-            android:id="@+id/action_splash_fragment_to_loginFragment"
+            android:id="@+id/action_splashFragment_to_loginFragment"
             app:destination="@id/login_pin_fragment"/>
     </fragment>
 
@@ -485,6 +485,10 @@
         <action
             android:id="@+id/action_joinCompleteFragment_to_pinFragment"
             app:destination="@id/login_pin_fragment" />
+        <action
+            android:id="@+id/action_joinCompleteFragment_to_homeFragment"
+            app:destination="@id/homeFragment"
+            />
     </fragment>
 
     <fragment