diff --git a/service/src/main/kotlin/com/sangdol/roomescape/schedule/business/ScheduleService.kt b/service/src/main/kotlin/com/sangdol/roomescape/schedule/business/ScheduleService.kt
index ff6c11ea..685b33a6 100644
--- a/service/src/main/kotlin/com/sangdol/roomescape/schedule/business/ScheduleService.kt
+++ b/service/src/main/kotlin/com/sangdol/roomescape/schedule/business/ScheduleService.kt
@@ -1,6 +1,8 @@
 package com.sangdol.roomescape.schedule.business
 
 import com.sangdol.common.persistence.IDGenerator
+import com.sangdol.common.utils.KoreaDate
+import com.sangdol.common.utils.KoreaTime
 import com.sangdol.roomescape.admin.business.AdminService
 import com.sangdol.roomescape.common.types.AuditingInfo
 import com.sangdol.roomescape.common.types.Auditor
@@ -44,7 +46,9 @@ class ScheduleService(
     @Transactional(readOnly = true)
     fun getStoreScheduleByDate(storeId: Long, date: LocalDate): ScheduleWithThemeListResponse {
         log.info { "[getStoreScheduleByDate] 매장 일정 조회: storeId=${storeId}, date=$date" }
-        val currentDate = LocalDate.now()
+
+        val currentDate: LocalDate = KoreaDate.today()
+        val currentTime: LocalTime = KoreaTime.now()
 
         if (date.isBefore(currentDate)) {
             log.warn { "[getStoreScheduleByDate] 이전 날짜 선택으로 인한 실패: date=${date}" }
@@ -53,7 +57,7 @@ class ScheduleService(
 
         val schedules: List<ScheduleOverview> =
             scheduleRepository.findStoreSchedulesWithThemeByDate(storeId, date)
-                .filter { it.date.isAfter(date) || (it.date.isEqual(date) && it.time.isAfter(LocalTime.now())) }
+                .filter { it.time.isAfter(currentTime) }
 
         return schedules.toResponse()
             .also {
@@ -89,7 +93,7 @@ class ScheduleService(
     fun searchSchedules(storeId: Long, date: LocalDate?, themeId: Long?): AdminScheduleSummaryListResponse {
         log.info { "[searchSchedules] 일정 검색 시작: storeId=$storeId, date=$date, themeId=$themeId" }
 
-        val searchDate = date ?: LocalDate.now()
+        val searchDate = date ?: KoreaDate.today()
 
         val schedules: List<ScheduleOverview> =
             scheduleRepository.findStoreSchedulesWithThemeByDate(storeId, searchDate)
diff --git a/service/src/main/kotlin/com/sangdol/roomescape/schedule/business/ScheduleValidator.kt b/service/src/main/kotlin/com/sangdol/roomescape/schedule/business/ScheduleValidator.kt
index 4b79cd1b..a9387348 100644
--- a/service/src/main/kotlin/com/sangdol/roomescape/schedule/business/ScheduleValidator.kt
+++ b/service/src/main/kotlin/com/sangdol/roomescape/schedule/business/ScheduleValidator.kt
@@ -1,5 +1,6 @@
 package com.sangdol.roomescape.schedule.business
 
+import com.sangdol.common.utils.KoreaDateTime
 import com.sangdol.roomescape.schedule.exception.ScheduleErrorCode
 import com.sangdol.roomescape.schedule.exception.ScheduleException
 import com.sangdol.roomescape.schedule.infrastructure.persistence.ScheduleEntity
@@ -13,6 +14,7 @@ import org.springframework.stereotype.Component
 import java.time.LocalDate
 import java.time.LocalDateTime
 import java.time.LocalTime
+import java.time.temporal.ChronoUnit
 
 private val log: KLogger = KotlinLogging.logger {}
 
@@ -56,9 +58,10 @@ class ScheduleValidator(
     }
 
     private fun validateNotInPast(date: LocalDate, time: LocalTime) {
-        val dateTime = LocalDateTime.of(date, time)
+        val now = KoreaDateTime.now().truncatedTo(ChronoUnit.MINUTES)
+        val inputDateTime = LocalDateTime.of(date, time).truncatedTo(ChronoUnit.MINUTES)
 
-        if (dateTime.isBefore(LocalDateTime.now())) {
+        if (inputDateTime.isBefore(now)) {
             log.info {
                 "[ScheduleValidator.validateDateTime] 이전 시간 선택으로 인한 실패: date=${date} / time=${time}"
             }
diff --git a/service/src/test/kotlin/com/sangdol/roomescape/schedule/AdminScheduleApiTest.kt b/service/src/test/kotlin/com/sangdol/roomescape/schedule/AdminScheduleApiTest.kt
index 1576bbca..b24fa2cc 100644
--- a/service/src/test/kotlin/com/sangdol/roomescape/schedule/AdminScheduleApiTest.kt
+++ b/service/src/test/kotlin/com/sangdol/roomescape/schedule/AdminScheduleApiTest.kt
@@ -1,10 +1,13 @@
 package com.sangdol.roomescape.schedule
 
-import com.sangdol.roomescape.common.types.Auditor
 import com.sangdol.common.types.web.HttpStatus
+import com.sangdol.common.utils.KoreaDate
+import com.sangdol.common.utils.KoreaDateTime
+import com.sangdol.common.utils.KoreaTime
 import com.sangdol.roomescape.admin.infrastructure.persistence.AdminPermissionLevel
 import com.sangdol.roomescape.admin.infrastructure.persistence.AdminType
 import com.sangdol.roomescape.auth.exception.AuthErrorCode
+import com.sangdol.roomescape.common.types.Auditor
 import com.sangdol.roomescape.schedule.exception.ScheduleErrorCode
 import com.sangdol.roomescape.schedule.infrastructure.persistence.ScheduleEntity
 import com.sangdol.roomescape.schedule.infrastructure.persistence.ScheduleRepository
@@ -54,7 +57,8 @@ class AdminScheduleApiTest(
                 lateinit var token: String
 
                 beforeTest {
-                    val today = LocalDate.now()
+                    val now = KoreaDateTime.now()
+                    val today = now.toLocalDate()
                     store = dummyInitializer.createStore()
                     val admin = AdminFixture.createStoreAdmin(storeId = store.id)
                     token = testAuthUtil.adminLogin(admin).second
@@ -66,21 +70,21 @@ class AdminScheduleApiTest(
                                     storeId = store.id,
                                     request = ScheduleFixture.createRequest.copy(
                                         date = today,
-                                        time = LocalTime.now().plusHours(2)
+                                        time = now.toLocalTime().plusHours(2)
                                     )
                                 ),
                                 dummyInitializer.createSchedule(
                                     storeId = store.id,
                                     request = ScheduleFixture.createRequest.copy(
                                         date = today,
-                                        time = LocalTime.now().plusHours(1)
+                                        time = now.toLocalTime().plusHours(1)
                                     )
                                 ),
                                 dummyInitializer.createSchedule(
                                     storeId = store.id,
                                     request = ScheduleFixture.createRequest.copy(
                                         date = today.plusDays(1),
-                                        time = LocalTime.of(11, 0)
+                                        time = LocalTime.of(10, 0)
                                     )
                                 )
                             )
@@ -95,7 +99,7 @@ class AdminScheduleApiTest(
                         },
                         expect = {
                             statusCode(HttpStatus.OK.value())
-                            body("data.schedules.size()", equalTo(schedules.filter { it.date.isEqual(LocalDate.now()) }.size))
+                            body("data.schedules.size()", equalTo(schedules.filter { it.date.isEqual(KoreaDate.today()) }.size))
                             assertProperties(
                                 props = setOf("id", "themeName", "startFrom", "endAt", "status"),
                                 propsNameIfList = "schedules"
@@ -386,8 +390,9 @@ class AdminScheduleApiTest(
 
             test("과거 시간을 선택하면 실패한다.") {
                 val (admin, token) = testAuthUtil.defaultStoreAdminLogin()
-                val date = LocalDate.now()
-                val time = LocalTime.now().minusMinutes(1)
+                val now = KoreaDateTime.now()
+                val date = now.toLocalDate()
+                val time = now.toLocalTime().minusMinutes(1)
                 val theme = dummyInitializer.createTheme()
 
                 val request = ScheduleFixture.createRequest.copy(date = date, time = time, themeId = theme.id)
@@ -490,29 +495,50 @@ class AdminScheduleApiTest(
             }
 
             context("정상 응답") {
-                test("시간만 변경한다.") {
-                    val (admin, token) = testAuthUtil.defaultStoreAdminLogin()
-                    val schedule = initialize("수정을 위한 일정 생성") {
-                        dummyInitializer.createSchedule()
-                    }
-                    val updateTime = schedule.time.plusHours(1)
-
-                    runTest(
-                        token = token,
-                        using = {
-                            body(ScheduleUpdateRequest(time = updateTime))
-                        },
-                        on = {
-                            patch("/admin/schedules/${schedule.id}")
-                        },
-                        expect = {
-                            statusCode(HttpStatus.OK.value())
+                context("시간만 변경한다.") {
+                    test("성공") {
+                        val (admin, token) = testAuthUtil.defaultStoreAdminLogin()
+                        val schedule = initialize("수정을 위한 일정 생성") {
+                            dummyInitializer.createSchedule()
                         }
-                    ).also {
-                        val updated = scheduleRepository.findByIdOrNull(schedule.id)!!
-                        updated.time shouldBe updateTime
-                        updated.status shouldBe schedule.status
-                        updated.updatedAt shouldNotBe schedule.updatedAt
+                        val updateTime = schedule.time.plusHours(1)
+
+                        runTest(
+                            token = token,
+                            using = {
+                                body(ScheduleUpdateRequest(time = updateTime))
+                            },
+                            on = {
+                                patch("/admin/schedules/${schedule.id}")
+                            },
+                            expect = {
+                                statusCode(HttpStatus.OK.value())
+                            }
+                        ).also {
+                            val updated = scheduleRepository.findByIdOrNull(schedule.id)!!
+                            updated.time shouldBe updateTime
+                            updated.status shouldBe schedule.status
+                            updated.updatedAt shouldNotBe schedule.updatedAt
+                        }
+                    }
+
+                    test("지난 시간을 선택하면 실패한다.") {
+                        val (admin, token) = testAuthUtil.defaultStoreAdminLogin()
+                        val schedule = initialize("수정을 위한 일정 생성") {
+                            val request = ScheduleFixture.createRequest.copy(
+                                date = KoreaDate.today(),
+                                time = KoreaTime.now().plusHours(1)
+                            )
+                            dummyInitializer.createSchedule(request = request)
+                        }
+
+                        runExceptionTest(
+                            token = token,
+                            method = HttpMethod.PATCH,
+                            endpoint = "/admin/schedules/${schedule.id}",
+                            requestBody = ScheduleUpdateRequest(time = KoreaTime.now().minusMinutes(1)),
+                            expectedErrorCode = ScheduleErrorCode.PAST_DATE_TIME
+                        )
                     }
                 }
 
diff --git a/service/src/test/kotlin/com/sangdol/roomescape/schedule/ScheduleApiTest.kt b/service/src/test/kotlin/com/sangdol/roomescape/schedule/ScheduleApiTest.kt
index 96453cff..b2532cf8 100644
--- a/service/src/test/kotlin/com/sangdol/roomescape/schedule/ScheduleApiTest.kt
+++ b/service/src/test/kotlin/com/sangdol/roomescape/schedule/ScheduleApiTest.kt
@@ -1,6 +1,8 @@
 package com.sangdol.roomescape.schedule
 
 import com.sangdol.common.types.web.HttpStatus
+import com.sangdol.common.utils.KoreaDate
+import com.sangdol.common.utils.KoreaTime
 import com.sangdol.roomescape.admin.infrastructure.persistence.AdminPermissionLevel
 import com.sangdol.roomescape.admin.infrastructure.persistence.AdminType
 import com.sangdol.roomescape.auth.exception.AuthErrorCode
@@ -13,16 +15,18 @@ import org.hamcrest.CoreMatchers.equalTo
 import org.springframework.data.repository.findByIdOrNull
 import org.springframework.http.HttpMethod
 import java.time.LocalDate
-import java.time.LocalTime
 
 class ScheduleApiTest(
     private val scheduleRepository: ScheduleRepository
 ) : FunSpecSpringbootTest() {
     init {
         context("특정 매장 + 날짜의 일정 및 테마 정보를 조회한다.") {
+            /**
+             * @throws 23시 57분 ~ 59분에 실행하면 실패함.
+             */
             test("날짜가 당일이면 현재 시간 이후의 정보만 조회된다.") {
                 val size = 3
-                val date = LocalDate.now()
+                val date = KoreaDate.today()
                 val store = dummyInitializer.createStore()
 
                 initialize("조회를 위한 오늘 날짜의 현재 시간 이후인 ${size}개의 일정, 현재 시간 이전인 1개의 일정 생성") {
@@ -31,7 +35,7 @@ class ScheduleApiTest(
                             storeId = store.id,
                             request = ScheduleFixture.createRequest.copy(
                                 date = date,
-                                time = LocalTime.now().plusMinutes(i.toLong())
+                                time = KoreaTime.now().plusMinutes(i.toLong())
                             )
                         )
                     }
@@ -40,22 +44,18 @@ class ScheduleApiTest(
                         storeId = store.id,
                         request = ScheduleFixture.createRequest.copy(
                             date = date,
-                            time = LocalTime.now().minusMinutes(1)
+                            time = KoreaTime.now().minusMinutes(1)
                         )
                     )
                 }
 
-                val expectedSize = scheduleRepository.findAll().takeIf { it.isNotEmpty() }
-                    ?.let { it.count { schedule -> schedule.date.isEqual(date) && schedule.time.isAfter(LocalTime.now()) } }
-                    ?: throw AssertionError("initialize 작업에서 레코드가 저장되지 않음.")
-
                 runTest(
                     on = {
                         get("/stores/${store.id}/schedules?date=${date}")
                     },
                     expect = {
                         statusCode(HttpStatus.OK.value())
-                        body("data.schedules.size()", equalTo(expectedSize))
+                        body("data.schedules.size()", equalTo(size))
                         assertProperties(
                             props = setOf("id", "startFrom", "endAt", "themeId", "themeName", "themeDifficulty", "status"),
                             propsNameIfList = "schedules"