diff --git a/src/main/java/com/gdschongik/gdsc/domain/study/domain/StudyDetailValidator.java b/src/main/java/com/gdschongik/gdsc/domain/study/domain/StudyDetailValidator.java
index e6a02f0f3..f6b75b698 100644
--- a/src/main/java/com/gdschongik/gdsc/domain/study/domain/StudyDetailValidator.java
+++ b/src/main/java/com/gdschongik/gdsc/domain/study/domain/StudyDetailValidator.java
@@ -30,11 +30,7 @@ private void validateStudyMentorAuthorization(Member member, StudyDetail studyDe
     }
 
     private void validateDeadLine(LocalDateTime deadline, LocalDateTime studyStartDate) {
-        if (deadline.isBefore(LocalDateTime.now())) {
-            throw new CustomException(ASSIGNMENT_DEADLINE_INVALID);
-        }
-
-        if (deadline.isBefore(studyStartDate)) {
+        if (deadline.isBefore(LocalDateTime.now()) || deadline.isBefore(studyStartDate)) {
             throw new CustomException(ASSIGNMENT_DEADLINE_INVALID);
         }
     }