diff --git a/src/test/kotlin/roomescape/member/controller/MemberControllerTest.kt b/src/test/kotlin/roomescape/member/controller/MemberControllerTest.kt
index 7a8cb84f..d7a55fbc 100644
--- a/src/test/kotlin/roomescape/member/controller/MemberControllerTest.kt
+++ b/src/test/kotlin/roomescape/member/controller/MemberControllerTest.kt
@@ -1,15 +1,19 @@
 package roomescape.member.controller
 
+import com.ninjasquad.springmockk.MockkBean
+import com.ninjasquad.springmockk.SpykBean
 import io.kotest.assertions.assertSoftly
 import io.kotest.matchers.collections.shouldContainAll
 import io.kotest.matchers.shouldBe
 import io.mockk.every
-import io.mockk.mockk
 import org.springframework.beans.factory.annotation.Autowired
 import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest
 import org.springframework.test.web.servlet.MockMvc
 import roomescape.auth.exception.AuthErrorCode
+import roomescape.member.business.MemberService
 import roomescape.member.exception.MemberErrorCode
+import roomescape.member.exception.MemberException
+import roomescape.member.implement.MemberWriter
 import roomescape.member.infrastructure.persistence.Role
 import roomescape.member.web.MemberController
 import roomescape.member.web.MemberRetrieveListResponse
@@ -23,11 +27,18 @@ class MemberControllerTest(
     @Autowired private val mockMvc: MockMvc
 ) : RoomescapeApiTest() {
 
+    @SpykBean
+    private lateinit var memberService: MemberService
+
+    @MockkBean
+    private lateinit var memberWriter: MemberWriter
+
+
     init {
         given("GET /members 요청을") {
             val endpoint = "/members"
 
-            every { memberRepository.findAll() } returns listOf(
+            every { memberFinder.findAll() } returns listOf(
                 MemberFixture.create(id = Random.nextLong(), name = "name1"),
                 MemberFixture.create(id = Random.nextLong(), name = "name2"),
                 MemberFixture.create(id = Random.nextLong(), name = "name3"),
@@ -96,11 +107,7 @@ class MemberControllerTest(
             )
             `when`("같은 이메일이 없으면") {
                 every {
-                    memberRepository.existsByEmail(request.email)
-                } returns false
-
-                every {
-                    memberRepository.save(any())
+                    memberWriter.create(any(), any(), any(), any())
                 } returns MemberFixture.create(
                     id = 1,
                     name = request.name,
@@ -124,8 +131,8 @@ class MemberControllerTest(
 
             `when`("같은 이메일이 있으면") {
                 every {
-                    memberRepository.existsByEmail(request.email)
-                } returns true
+                    memberWriter.create(request.name, request.email, request.password, Role.MEMBER)
+                } throws MemberException(MemberErrorCode.DUPLICATE_EMAIL)
 
                 then("에러 응답") {
                     val expectedError = MemberErrorCode.DUPLICATE_EMAIL
@@ -138,7 +145,6 @@ class MemberControllerTest(
                         status { isEqualTo(expectedError.httpStatus.value()) }
                         jsonPath("$.code") { value(expectedError.errorCode) }
                     }
-
                 }
             }
         }
diff --git a/src/test/kotlin/roomescape/util/RoomescapeApiTest.kt b/src/test/kotlin/roomescape/util/RoomescapeApiTest.kt
index 9a038941..aaa2af4c 100644
--- a/src/test/kotlin/roomescape/util/RoomescapeApiTest.kt
+++ b/src/test/kotlin/roomescape/util/RoomescapeApiTest.kt
@@ -11,7 +11,6 @@ import org.springframework.context.annotation.Bean
 import org.springframework.context.annotation.Import
 import org.springframework.context.annotation.Primary
 import org.springframework.data.jpa.mapping.JpaMetamodelMappingContext
-import org.springframework.data.repository.findByIdOrNull
 import org.springframework.http.HttpHeaders
 import org.springframework.http.MediaType
 import org.springframework.test.web.servlet.*
@@ -22,7 +21,9 @@ import roomescape.auth.web.support.AuthInterceptor
 import roomescape.auth.web.support.MemberIdResolver
 import roomescape.common.config.JacksonConfig
 import roomescape.common.log.ApiLogMessageConverter
-import roomescape.member.business.MemberService
+import roomescape.member.exception.MemberErrorCode
+import roomescape.member.exception.MemberException
+import roomescape.member.implement.MemberFinder
 import roomescape.member.infrastructure.persistence.MemberEntity
 import roomescape.member.infrastructure.persistence.MemberRepository
 import roomescape.util.MemberFixture.NOT_LOGGED_IN_USERID
@@ -37,14 +38,14 @@ abstract class RoomescapeApiTest : BehaviorSpec() {
     @SpykBean
     private lateinit var memberIdResolver: MemberIdResolver
 
-    @SpykBean
-    lateinit var memberService: MemberService
+    @MockkBean
+    private lateinit var memberRepository: MemberRepository
 
     @SpykBean
     lateinit var apiLogMessageConverter: ApiLogMessageConverter
 
-    @MockkBean
-    lateinit var memberRepository: MemberRepository
+    @SpykBean
+    lateinit var memberFinder: MemberFinder
 
     @MockkBean
     lateinit var jwtHandler: JwtHandler
@@ -96,8 +97,7 @@ abstract class RoomescapeApiTest : BehaviorSpec() {
             jwtHandler.getMemberIdFromToken(any())
         } returns admin.id!!
 
-        every { memberRepository.existsById(admin.id!!) } returns true
-        every { memberRepository.findByIdOrNull(admin.id!!) } returns admin
+        every { memberFinder.findById(admin.id!!) } returns admin
     }
 
     fun loginAsUser() {
@@ -105,8 +105,7 @@ abstract class RoomescapeApiTest : BehaviorSpec() {
             jwtHandler.getMemberIdFromToken(any())
         } returns user.id!!
 
-        every { memberRepository.existsById(user.id!!) } returns true
-        every { memberRepository.findByIdOrNull(user.id!!) } returns user
+        every { memberFinder.findById(user.id!!) } returns user
     }
 
     fun doNotLogin() {
@@ -114,8 +113,9 @@ abstract class RoomescapeApiTest : BehaviorSpec() {
             jwtHandler.getMemberIdFromToken(any())
         } throws AuthException(AuthErrorCode.INVALID_TOKEN)
 
-        every { memberRepository.existsById(NOT_LOGGED_IN_USERID) } returns false
-        every { memberRepository.findByIdOrNull(NOT_LOGGED_IN_USERID) } returns null
+        every {
+            memberFinder.findById(NOT_LOGGED_IN_USERID)
+        } throws MemberException(MemberErrorCode.MEMBER_NOT_FOUND)
     }
 
     fun <T> MvcResult.readValue(valueType: Class<T>): T = this.response.contentAsString