diff --git a/app/src/main/java/org/android/go/sopt/data/entity/remote/request/RequestPostSignInDto.kt b/app/src/main/java/org/android/go/sopt/data/entity/remote/request/RequestPostSignInDto.kt
new file mode 100644
index 0000000..bc7a894
--- /dev/null
+++ b/app/src/main/java/org/android/go/sopt/data/entity/remote/request/RequestPostSignInDto.kt
@@ -0,0 +1,12 @@
+package org.android.go.sopt.data.entity.remote.request
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class RequestPostSignInDto(
+    @SerialName("id")
+    val id: String,
+    @SerialName("password")
+    val password: String,
+)
diff --git a/app/src/main/java/org/android/go/sopt/data/entity/remote/response/ResponsePostSignInDto.kt b/app/src/main/java/org/android/go/sopt/data/entity/remote/response/ResponsePostSignInDto.kt
new file mode 100644
index 0000000..01e6ed2
--- /dev/null
+++ b/app/src/main/java/org/android/go/sopt/data/entity/remote/response/ResponsePostSignInDto.kt
@@ -0,0 +1,14 @@
+package org.android.go.sopt.data.entity.remote.response
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class ResponsePostSignInDto(
+    @SerialName("id")
+    val id: String,
+    @SerialName("name")
+    val name: String,
+    @SerialName("skill")
+    val skill: String?,
+)
diff --git a/app/src/main/java/org/android/go/sopt/data/repository/AuthRepositoryImpl.kt b/app/src/main/java/org/android/go/sopt/data/repository/AuthRepositoryImpl.kt
index b0524d0..5ccc43d 100644
--- a/app/src/main/java/org/android/go/sopt/data/repository/AuthRepositoryImpl.kt
+++ b/app/src/main/java/org/android/go/sopt/data/repository/AuthRepositoryImpl.kt
@@ -1,6 +1,8 @@
 package org.android.go.sopt.data.repository
 
+import org.android.go.sopt.data.entity.remote.request.RequestPostSignInDto
 import org.android.go.sopt.data.entity.remote.request.RequestPostSignUpDto
+import org.android.go.sopt.data.entity.remote.response.ResponsePostSignInDto
 import org.android.go.sopt.data.entity.remote.response.ResponsePostSignUpDto
 import org.android.go.sopt.data.source.local.SharedPrefDataSource
 import org.android.go.sopt.data.source.remote.AuthDataSource
@@ -17,6 +19,11 @@ class AuthRepositoryImpl @Inject constructor(
             authDataSource.postSignup(requestPostSignUpDto).data
         }
 
+    override suspend fun postSignin(requestPostSignInDto: RequestPostSignInDto): Result<ResponsePostSignInDto?> =
+        runCatching {
+            authDataSource.postSignIn(requestPostSignInDto).data
+        }
+
     override fun setAutoLogin(isAutoLogin: Boolean) {
         sharedPrefDataSource.isAutoLogin = isAutoLogin
     }
diff --git a/app/src/main/java/org/android/go/sopt/data/service/AuthService.kt b/app/src/main/java/org/android/go/sopt/data/service/AuthService.kt
index 9dd01c1..233e16a 100644
--- a/app/src/main/java/org/android/go/sopt/data/service/AuthService.kt
+++ b/app/src/main/java/org/android/go/sopt/data/service/AuthService.kt
@@ -1,6 +1,8 @@
 package org.android.go.sopt.data.service
 
+import org.android.go.sopt.data.entity.remote.request.RequestPostSignInDto
 import org.android.go.sopt.data.entity.remote.request.RequestPostSignUpDto
+import org.android.go.sopt.data.entity.remote.response.ResponsePostSignInDto
 import org.android.go.sopt.data.entity.remote.response.ResponsePostSignUpDto
 import org.android.go.sopt.data.entity.remote.response.wrapper.BaseResponse
 import retrofit2.http.Body
@@ -11,4 +13,9 @@ interface AuthService {
     suspend fun postSignUp(
         @Body requestPostSignUpDto: RequestPostSignUpDto,
     ): BaseResponse<ResponsePostSignUpDto>
+
+    @POST("sign-in")
+    suspend fun postSignIn(
+        @Body requestPostSignInDto: RequestPostSignInDto,
+    ): BaseResponse<ResponsePostSignInDto>
 }
diff --git a/app/src/main/java/org/android/go/sopt/data/source/remote/AuthDataSource.kt b/app/src/main/java/org/android/go/sopt/data/source/remote/AuthDataSource.kt
index 0c448a9..1f993cd 100644
--- a/app/src/main/java/org/android/go/sopt/data/source/remote/AuthDataSource.kt
+++ b/app/src/main/java/org/android/go/sopt/data/source/remote/AuthDataSource.kt
@@ -1,6 +1,8 @@
 package org.android.go.sopt.data.source.remote
 
+import org.android.go.sopt.data.entity.remote.request.RequestPostSignInDto
 import org.android.go.sopt.data.entity.remote.request.RequestPostSignUpDto
+import org.android.go.sopt.data.entity.remote.response.ResponsePostSignInDto
 import org.android.go.sopt.data.entity.remote.response.ResponsePostSignUpDto
 import org.android.go.sopt.data.entity.remote.response.wrapper.BaseResponse
 import org.android.go.sopt.data.service.AuthService
@@ -13,4 +15,9 @@ class AuthDataSource @Inject constructor(
         requestPostSignUpDto: RequestPostSignUpDto,
     ): BaseResponse<ResponsePostSignUpDto> =
         authService.postSignUp(requestPostSignUpDto)
+
+    suspend fun postSignIn(
+        requestPostSignInDto: RequestPostSignInDto,
+    ): BaseResponse<ResponsePostSignInDto> =
+        authService.postSignIn(requestPostSignInDto)
 }
diff --git a/app/src/main/java/org/android/go/sopt/domain/model/User.kt b/app/src/main/java/org/android/go/sopt/domain/model/User.kt
index 6fa189b..358915a 100644
--- a/app/src/main/java/org/android/go/sopt/domain/model/User.kt
+++ b/app/src/main/java/org/android/go/sopt/domain/model/User.kt
@@ -8,5 +8,5 @@ data class User(
     val id: String = "",
     val pwd: String = "",
     val name: String = "익명",
-    val specialty: String = "",
+    val specialty: String? = "",
 ) : Parcelable
diff --git a/app/src/main/java/org/android/go/sopt/domain/repository/AuthRepository.kt b/app/src/main/java/org/android/go/sopt/domain/repository/AuthRepository.kt
index f19542b..319a4da 100644
--- a/app/src/main/java/org/android/go/sopt/domain/repository/AuthRepository.kt
+++ b/app/src/main/java/org/android/go/sopt/domain/repository/AuthRepository.kt
@@ -1,12 +1,16 @@
 package org.android.go.sopt.domain.repository
 
+import org.android.go.sopt.data.entity.remote.request.RequestPostSignInDto
 import org.android.go.sopt.data.entity.remote.request.RequestPostSignUpDto
+import org.android.go.sopt.data.entity.remote.response.ResponsePostSignInDto
 import org.android.go.sopt.data.entity.remote.response.ResponsePostSignUpDto
 import org.android.go.sopt.domain.model.User
 
 interface AuthRepository {
     suspend fun postSignup(requestPostSignUpDto: RequestPostSignUpDto): Result<ResponsePostSignUpDto?>
 
+    suspend fun postSignin(requestPostSignInDto: RequestPostSignInDto): Result<ResponsePostSignInDto?>
+
     fun setAutoLogin(isAutoLogin: Boolean)
 
     fun getAutoLogin(): Boolean
diff --git a/app/src/main/java/org/android/go/sopt/presentation/login/LoginViewModel.kt b/app/src/main/java/org/android/go/sopt/presentation/login/LoginViewModel.kt
index 7f77ed1..e49b601 100644
--- a/app/src/main/java/org/android/go/sopt/presentation/login/LoginViewModel.kt
+++ b/app/src/main/java/org/android/go/sopt/presentation/login/LoginViewModel.kt
@@ -3,11 +3,17 @@ package org.android.go.sopt.presentation.login
 import androidx.lifecycle.LiveData
 import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
 import dagger.hilt.android.lifecycle.HiltViewModel
+import kotlinx.coroutines.launch
+import org.android.go.sopt.data.entity.remote.request.RequestPostSignInDto
+import org.android.go.sopt.domain.model.User
 import org.android.go.sopt.domain.repository.AuthRepository
 import org.android.go.sopt.util.state.LocalUiState
 import org.android.go.sopt.util.state.LocalUiState.Failure
 import org.android.go.sopt.util.state.LocalUiState.Success
+import retrofit2.HttpException
+import timber.log.Timber
 import javax.inject.Inject
 
 @HiltViewModel
@@ -18,8 +24,13 @@ class LoginViewModel @Inject constructor(
     val loginState: LiveData<LocalUiState>
         get() = _loginState
 
-    val id = MutableLiveData("")
-    val pwd = MutableLiveData("")
+    val _id = MutableLiveData("")
+    private val id: String
+        get() = _id.value?.trim() ?: ""
+
+    val _pwd = MutableLiveData("")
+    private val pwd: String
+        get() = _pwd.value?.trim() ?: ""
 
     init {
         setupAutoLogin()
@@ -31,15 +42,38 @@ class LoginViewModel @Inject constructor(
         }
     }
 
-    private fun isValidInput() = !id.value.isNullOrBlank() && !pwd.value.isNullOrBlank()
+    private fun isValidInput() = id.isNotBlank() && pwd.isNotBlank()
 
     fun login() {
         if (!isValidInput()) {
             _loginState.value = Failure(null)
             return
         }
-        // TODO : 로그인 정보 저장
-        authRepository.setAutoLogin(true)
-        _loginState.value = Success
+
+        val requestPostSignInDto = RequestPostSignInDto(
+            id = id,
+            password = pwd,
+        )
+        viewModelScope.launch {
+            authRepository.postSignin(requestPostSignInDto)
+                .onSuccess { response ->
+                    authRepository.setSignedUpUser(
+                        User(
+                            id = requestPostSignInDto.id,
+                            pwd = requestPostSignInDto.password,
+                            name = requireNotNull(response).name,
+                            specialty = response.skill,
+                        ),
+                    )
+                    authRepository.setAutoLogin(true)
+                    _loginState.value = Success
+                    Timber.d("POST SIGNIN SUCCESS : $response")
+                }
+                .onFailure { t ->
+                    if (t is HttpException) {
+                        Timber.e("POST SIGNIN FAIL ${t.code()} : ${t.message()}")
+                    }
+                }
+        }
     }
 }
diff --git a/app/src/main/res/layout/activity_login.xml b/app/src/main/res/layout/activity_login.xml
index e722c17..7fc435a 100644
--- a/app/src/main/res/layout/activity_login.xml
+++ b/app/src/main/res/layout/activity_login.xml
@@ -50,7 +50,7 @@
             android:imeOptions="actionNext"
             android:inputType="text"
             android:paddingVertical="16dp"
-            android:text="@={vm.id}"
+            android:text="@={vm._id}"
             android:textAppearance="?textAppearanceBodyLarge"
             app:layout_constraintEnd_toEndOf="parent"
             app:layout_constraintStart_toStartOf="parent"
@@ -78,7 +78,7 @@
             android:imeOptions="actionDone"
             android:inputType="textPassword"
             android:paddingVertical="16dp"
-            android:text="@={vm.pwd}"
+            android:text="@={vm._pwd}"
             android:textAppearance="?textAppearanceBodyLarge"
             app:layout_constraintEnd_toEndOf="parent"
             app:layout_constraintStart_toStartOf="parent"