diff --git a/adapters/in-web/src/main/kotlin/com/pokit/auth/model/PrincipalUser.kt b/adapters/in-web/src/main/kotlin/com/pokit/auth/model/PrincipalUser.kt
index 36152fa7..6d4693f0 100644
--- a/adapters/in-web/src/main/kotlin/com/pokit/auth/model/PrincipalUser.kt
+++ b/adapters/in-web/src/main/kotlin/com/pokit/auth/model/PrincipalUser.kt
@@ -11,7 +11,8 @@ data class PrincipalUser(
     val id: Long,
     val email: String,
     val role: Role,
-    val authPlatform: AuthPlatform
+    val authPlatform: AuthPlatform,
+    val sub: String?
 ) : UserDetails {
     companion object {
         fun of(user: User) =
@@ -19,7 +20,8 @@ data class PrincipalUser(
                 id = user.id,
                 email = user.email,
                 role = user.role,
-                authPlatform = user.authPlatform
+                authPlatform = user.authPlatform,
+                sub = user.sub
             )
     }
 
@@ -36,4 +38,4 @@ data class PrincipalUser(
     }
 }
 
-fun PrincipalUser.toDomain() = User(id = this.id, email = this.email, role = this.role, authPlatform = this.authPlatform)
+fun PrincipalUser.toDomain() = User(id = this.id, email = this.email, role = this.role, authPlatform = this.authPlatform, sub = this.sub)
diff --git a/adapters/out-persistence/src/main/kotlin/com/pokit/out/persistence/user/impl/UserAdapter.kt b/adapters/out-persistence/src/main/kotlin/com/pokit/out/persistence/user/impl/UserAdapter.kt
index 0c93e3eb..bbf7fe89 100644
--- a/adapters/out-persistence/src/main/kotlin/com/pokit/out/persistence/user/impl/UserAdapter.kt
+++ b/adapters/out-persistence/src/main/kotlin/com/pokit/out/persistence/user/impl/UserAdapter.kt
@@ -19,8 +19,8 @@ class UserAdapter(
         return savedUser.toDomain()
     }
 
-    override fun loadByEmailAndAuthPlatform(email: String, authPlatform: AuthPlatform) =
-        userRepository.findByEmailAndAuthPlatformAndDeleted(email, authPlatform, false)
+    override fun loadBySubAndAuthPlatform(sub: String, authPlatform: AuthPlatform) =
+        userRepository.findBySubAndAuthPlatformAndDeleted(sub, authPlatform, false)
         ?.run { toDomain() }
 
     override fun loadById(id: Long) = userRepository.findByIdAndDeleted(id, false)
@@ -36,4 +36,7 @@ class UserAdapter(
         userRepository.findByDeleted(false)
             .map { it.id }
 
+    override fun loadByEmailAndAuthPlatform(email: String, authPlatform: AuthPlatform) =
+        userRepository.findByEmailAndAuthPlatformAndDeleted(email, authPlatform, false)
+            ?.run { toDomain() }
 }
diff --git a/adapters/out-persistence/src/main/kotlin/com/pokit/out/persistence/user/persist/UserEntity.kt b/adapters/out-persistence/src/main/kotlin/com/pokit/out/persistence/user/persist/UserEntity.kt
index abf1c0d8..e4552475 100644
--- a/adapters/out-persistence/src/main/kotlin/com/pokit/out/persistence/user/persist/UserEntity.kt
+++ b/adapters/out-persistence/src/main/kotlin/com/pokit/out/persistence/user/persist/UserEntity.kt
@@ -32,7 +32,10 @@ class UserEntity(
     var deleted: Boolean = false,
 
     @Column(name = "is_registered")
-    var registered: Boolean
+    var registered: Boolean,
+
+    @Column(name = "sub")
+    var sub: String?
 ) : BaseEntity() {
     fun delete() {
         this.deleted = true
@@ -46,7 +49,8 @@ class UserEntity(
                 role = user.role,
                 nickname = user.nickName,
                 authPlatform = user.authPlatform,
-                registered = user.registered
+                registered = user.registered,
+                sub = user.sub
             )
     }
 }
@@ -57,5 +61,6 @@ fun UserEntity.toDomain() = User(
     role = this.role,
     nickName = this.nickname,
     authPlatform = this.authPlatform,
-    registered = this.registered
+    registered = this.registered,
+    sub = this.sub
 )
diff --git a/adapters/out-persistence/src/main/kotlin/com/pokit/out/persistence/user/persist/UserRepository.kt b/adapters/out-persistence/src/main/kotlin/com/pokit/out/persistence/user/persist/UserRepository.kt
index c17a9dd3..0ffddccf 100644
--- a/adapters/out-persistence/src/main/kotlin/com/pokit/out/persistence/user/persist/UserRepository.kt
+++ b/adapters/out-persistence/src/main/kotlin/com/pokit/out/persistence/user/persist/UserRepository.kt
@@ -4,11 +4,13 @@ import com.pokit.token.model.AuthPlatform
 import org.springframework.data.jpa.repository.JpaRepository
 
 interface UserRepository : JpaRepository<UserEntity, Long> {
-    fun findByEmailAndAuthPlatformAndDeleted(email: String,authPlatform: AuthPlatform, deleted: Boolean): UserEntity?
+    fun findBySubAndAuthPlatformAndDeleted(sub: String, authPlatform: AuthPlatform, deleted: Boolean): UserEntity?
 
     fun existsByNickname(nickname: String): Boolean
 
     fun findByIdAndDeleted(id: Long, deleted: Boolean): UserEntity?
 
     fun findByDeleted(deleted: Boolean): List<UserEntity>
+
+    fun findByEmailAndAuthPlatformAndDeleted(email: String, authPlatform: AuthPlatform, deleted: Boolean): UserEntity?
 }
diff --git a/adapters/out-persistence/src/testFixtures/kotlin/com/pokit/user/UserFixture.kt b/adapters/out-persistence/src/testFixtures/kotlin/com/pokit/user/UserFixture.kt
index cf07c117..dbb631c9 100644
--- a/adapters/out-persistence/src/testFixtures/kotlin/com/pokit/user/UserFixture.kt
+++ b/adapters/out-persistence/src/testFixtures/kotlin/com/pokit/user/UserFixture.kt
@@ -9,11 +9,11 @@ import com.pokit.user.model.User
 
 class UserFixture {
     companion object {
-        fun getUser() = User(1L, "ij@naver.com", Role.USER, authPlatform = AuthPlatform.GOOGLE)
+        fun getUser() = User(1L, "ij@naver.com", Role.USER, authPlatform = AuthPlatform.GOOGLE, sub = "asdasd")
 
-        fun getUserInfo() = UserInfo("ig@naver.com", AuthPlatform.GOOGLE)
+        fun getUserInfo() = UserInfo("ig@naver.com", AuthPlatform.GOOGLE, sub = "asdasd")
 
-        fun getInvalidUser() = User(2L, "dls@naver.com", Role.USER, authPlatform = AuthPlatform.GOOGLE)
+        fun getInvalidUser() = User(2L, "dls@naver.com", Role.USER, authPlatform = AuthPlatform.GOOGLE, sub = "sub")
 
         fun getSignUpRequest() = SignUpRequest("인주니", listOf(InterestType.SPORTS))
     }
diff --git a/adapters/out-web/src/main/kotlin/com/pokit/auth/common/dto/GoogleUserResponse.kt b/adapters/out-web/src/main/kotlin/com/pokit/auth/common/dto/GoogleUserResponse.kt
index 96660de6..26a7b199 100644
--- a/adapters/out-web/src/main/kotlin/com/pokit/auth/common/dto/GoogleUserResponse.kt
+++ b/adapters/out-web/src/main/kotlin/com/pokit/auth/common/dto/GoogleUserResponse.kt
@@ -1,5 +1,6 @@
 package com.pokit.auth.common.dto
 
 data class GoogleUserResponse(
-    val email: String
+    val email: String,
+    val sub: String
 )
diff --git a/adapters/out-web/src/main/kotlin/com/pokit/auth/impl/AppleApiAdapter.kt b/adapters/out-web/src/main/kotlin/com/pokit/auth/impl/AppleApiAdapter.kt
index 9502a06c..3a589791 100644
--- a/adapters/out-web/src/main/kotlin/com/pokit/auth/impl/AppleApiAdapter.kt
+++ b/adapters/out-web/src/main/kotlin/com/pokit/auth/impl/AppleApiAdapter.kt
@@ -25,8 +25,8 @@ class AppleApiAdapter(
     override fun getUserInfo(idToken: String): UserInfo {
         val claims = decodeAndVerifyIdToken(idToken) // id token을 통해 사용자 정보 추출
         val email = claims["email"] as String
-
-        return UserInfo(email = email, authPlatform = AuthPlatform.APPLE)
+        val sub = claims["sub"] as String
+        return UserInfo(email = email, authPlatform = AuthPlatform.APPLE, sub = sub)
     }
 
     override fun revoke(refreshToken: String) {
@@ -38,7 +38,7 @@ class AppleApiAdapter(
         revokeAuth(refreshToken, clientSecret)
     }
 
-    private fun decodeAndVerifyIdToken(idToken: String): Map<String, Any> {
+    private fun decodeAndVerifyIdToken(idToken: String): Map<String, Any?> {
         val publicKeys = appleFeignClient.getApplePublicKeys()
 
         val header = appleTokenParser.parseHeader(idToken)
diff --git a/adapters/out-web/src/main/kotlin/com/pokit/auth/impl/GoogleApiAdapter.kt b/adapters/out-web/src/main/kotlin/com/pokit/auth/impl/GoogleApiAdapter.kt
index 09ac316f..b2a3f22a 100644
--- a/adapters/out-web/src/main/kotlin/com/pokit/auth/impl/GoogleApiAdapter.kt
+++ b/adapters/out-web/src/main/kotlin/com/pokit/auth/impl/GoogleApiAdapter.kt
@@ -1,6 +1,5 @@
 package com.pokit.auth.impl
 
-import com.pokit.auth.common.property.GoogleProperty
 import com.pokit.auth.common.support.GoogleFeignClient
 import com.pokit.auth.port.out.GoogleApiClient
 import com.pokit.common.exception.ClientValidationException
@@ -19,12 +18,13 @@ class GoogleApiAdapter(
 
         return UserInfo(
             email = response.email,
-            authPlatform = AuthPlatform.GOOGLE
+            authPlatform = AuthPlatform.GOOGLE,
+            sub = response.sub
         )
     }
 
     override fun revoke(refreshToken: String) {
-        if(refreshToken.isBlank()) {
+        if (refreshToken.isBlank()) {
             return
         }
         val revokeResponse = googleFeignClient.revoke(refreshToken)
diff --git a/application/src/main/kotlin/com/pokit/auth/port/service/AuthService.kt b/application/src/main/kotlin/com/pokit/auth/port/service/AuthService.kt
index 3be93345..3cecac09 100644
--- a/application/src/main/kotlin/com/pokit/auth/port/service/AuthService.kt
+++ b/application/src/main/kotlin/com/pokit/auth/port/service/AuthService.kt
@@ -37,8 +37,9 @@ class AuthService(
                 AuthPlatform.GOOGLE -> googleApiClient.getUserInfo(request.idToken)
                 AuthPlatform.APPLE -> appleApiClient.getUserInfo(request.idToken)
             }
-
-        val user = userPort.loadByEmailAndAuthPlatform(userInfo.email, platformType) ?: createUser(userInfo) // 없으면 저장
+        val user = userPort.loadBySubAndAuthPlatform(userInfo.sub, platformType)
+            ?: getUserByEmail(userInfo) // 기존 로그인 유저용, 추후 제거
+            ?: createUser(userInfo) // 없으면 저장
 
         val token = tokenProvider.createToken(user.id)
 
@@ -63,7 +64,26 @@ class AuthService(
     }
 
     private fun createUser(userInfo: UserInfo): User {
-        val user = User(email = userInfo.email, role = Role.USER, authPlatform = userInfo.authPlatform)
+        val user = User(
+            email = userInfo.email!!, // 존재하지 않았던 유저면 이메일 항상 존재
+            role = Role.USER,
+            authPlatform = userInfo.authPlatform,
+            sub = userInfo.sub
+        )
         return userPort.persist(user)
     }
+
+    private fun getUserByEmail(userInfo: UserInfo): User? {
+        val userEmail = userInfo.email
+
+        return if(userEmail == null) {
+            return null
+        } else {
+            val user = userPort.loadByEmailAndAuthPlatform(userEmail, userInfo.authPlatform)
+            user?.let {
+                it.insertSub(userInfo.sub)
+                userPort.persist(user)
+            }
+        }
+    }
 }
diff --git a/application/src/main/kotlin/com/pokit/user/port/out/UserPort.kt b/application/src/main/kotlin/com/pokit/user/port/out/UserPort.kt
index a106e4a6..4a9daaa0 100644
--- a/application/src/main/kotlin/com/pokit/user/port/out/UserPort.kt
+++ b/application/src/main/kotlin/com/pokit/user/port/out/UserPort.kt
@@ -6,7 +6,7 @@ import com.pokit.user.model.User
 interface UserPort {
     fun persist(user: User): User
 
-    fun loadByEmailAndAuthPlatform(email: String, authPlatform: AuthPlatform): User?
+    fun loadBySubAndAuthPlatform(sub: String, authPlatform: AuthPlatform): User?
 
     fun loadById(id: Long): User?
 
@@ -15,4 +15,6 @@ interface UserPort {
     fun delete(user: User)
 
     fun loadAllIds(): List<Long>
+
+    fun loadByEmailAndAuthPlatform(email: String, authPlatform: AuthPlatform): User?
 }
diff --git a/domain/src/main/kotlin/com/pokit/user/dto/UserInfo.kt b/domain/src/main/kotlin/com/pokit/user/dto/UserInfo.kt
index 91377695..a126c15c 100644
--- a/domain/src/main/kotlin/com/pokit/user/dto/UserInfo.kt
+++ b/domain/src/main/kotlin/com/pokit/user/dto/UserInfo.kt
@@ -3,6 +3,7 @@ package com.pokit.user.dto
 import com.pokit.token.model.AuthPlatform
 
 data class UserInfo(
-    val email: String,
-    val authPlatform: AuthPlatform
+    var email: String?,
+    val authPlatform: AuthPlatform,
+    val sub: String
 )
diff --git a/domain/src/main/kotlin/com/pokit/user/model/User.kt b/domain/src/main/kotlin/com/pokit/user/model/User.kt
index 27fe5fb4..92ed9793 100644
--- a/domain/src/main/kotlin/com/pokit/user/model/User.kt
+++ b/domain/src/main/kotlin/com/pokit/user/model/User.kt
@@ -11,13 +11,18 @@ data class User(
     val role: Role,
     var nickName: String = email,
     val authPlatform: AuthPlatform,
-    var registered: Boolean = false
+    var registered: Boolean = false,
+    var sub: String?
 ) {
     fun register(nickName: String) {
         this.nickName = nickName
         this.registered = true
     }
 
+    fun insertSub(sub: String) {
+        this.sub = sub
+    }
+
     fun modifyNickname(nickName: String) {
         this.nickName = nickName
     }