diff --git a/src/main/java/in/koreatech/koin/domain/timetable/dto/TimetableResponse.java b/src/main/java/in/koreatech/koin/domain/timetable/dto/TimetableResponse.java
index 7040abfcf..7eaf891b7 100644
--- a/src/main/java/in/koreatech/koin/domain/timetable/dto/TimetableResponse.java
+++ b/src/main/java/in/koreatech/koin/domain/timetable/dto/TimetableResponse.java
@@ -119,10 +119,7 @@ public static List<InnerTimetableResponse> from(List<TimetableLecture> timetable
         }
 
         private static boolean isValidClassTime(int classTime) {
-            if (classTime < 100) {
-                return classTime < 19;
-            }
-            return classTime % 100 < 19;
+            return classTime < 19 || classTime % 100 < 19;
         }
     }