diff --git a/src/main/java/org/cotato/csquiz/api/session/dto/UpdateSessionRequest.java b/src/main/java/org/cotato/csquiz/api/session/dto/UpdateSessionRequest.java
index bde86c08..c1608383 100644
--- a/src/main/java/org/cotato/csquiz/api/session/dto/UpdateSessionRequest.java
+++ b/src/main/java/org/cotato/csquiz/api/session/dto/UpdateSessionRequest.java
@@ -1,6 +1,10 @@
 package org.cotato.csquiz.api.session.dto;
 
+import static org.cotato.csquiz.domain.attendance.enums.DeadLine.DEFAULT_ATTENDANCE_DEADLINE;
+import static org.cotato.csquiz.domain.attendance.enums.DeadLine.DEFAULT_LATE_DEADLINE;
+
 import java.time.LocalDate;
+import java.util.Objects;
 import org.cotato.csquiz.api.attendance.dto.AttendanceDeadLineDto;
 import org.cotato.csquiz.domain.attendance.embedded.Location;
 import org.cotato.csquiz.domain.generation.enums.CSEducation;
@@ -28,4 +32,10 @@ public record UpdateSessionRequest(
         @NotNull
         DevTalk devTalk
 ) {
+    public UpdateSessionRequest {
+        if (Objects.isNull(attendTime)) {
+            attendTime = new AttendanceDeadLineDto(DEFAULT_ATTENDANCE_DEADLINE.getTime(),
+                    DEFAULT_LATE_DEADLINE.getTime());
+        }
+    }
 }
diff --git a/src/main/java/org/cotato/csquiz/domain/generation/service/SessionService.java b/src/main/java/org/cotato/csquiz/domain/generation/service/SessionService.java
index 18dacacd..e0aef929 100644
--- a/src/main/java/org/cotato/csquiz/domain/generation/service/SessionService.java
+++ b/src/main/java/org/cotato/csquiz/domain/generation/service/SessionService.java
@@ -131,6 +131,7 @@ public void updateSessionDate(Session session, LocalDate newDate, AttendanceDead
         Attendance findAttendance = attendanceRepository.findBySessionId(session.getId())
                 .orElseThrow(() -> new EntityNotFoundException("해당 세션의 출석이 존재하지 않습니다"));
 
+
         // 날짜가 바뀌지 않았고, 출결 시간이 모두 동일한 경우
         if (newDate.equals(session.getSessionDate()) &&
                 findAttendance.getAttendanceDeadLine().toLocalTime().equals(newDeadline.attendanceDeadLine()) &&
@@ -140,7 +141,7 @@ public void updateSessionDate(Session session, LocalDate newDate, AttendanceDead
         session.updateSessionDate(newDate);
 
         LocalDateTime newAttendanceDeadline = LocalDateTime.of(newDate, newDeadline.attendanceDeadLine());
-        LocalDateTime newLateDeadline = LocalDateTime.of(newDate, newDeadline.attendanceDeadLine());
+        LocalDateTime newLateDeadline = LocalDateTime.of(newDate, newDeadline.lateDeadLine());
         findAttendance.updateDeadLine(newAttendanceDeadline, newLateDeadline);
 
         attendanceRecordService.updateAttendanceStatus(findAttendance);