diff --git a/lib/screens/teacher_attendance_page.dart b/lib/screens/teacher_attendance_page.dart
index 9073a46..c065f69 100644
--- a/lib/screens/teacher_attendance_page.dart
+++ b/lib/screens/teacher_attendance_page.dart
@@ -391,6 +391,17 @@ class _TeacherAttendancePageState extends State<TeacherAttendancePage> {
     return result;
   }
 
+  /// 지금까지(오늘 이전 포함) 단 한 번이라도 태깅한 적 있는 학생 학번 집합.
+  /// (오늘 미제출인 학생 중에서도 "한 번도 태깅 안 해본 애"를 구분하기 위함)
+  Set<String> get _everCheckedInStudentIds {
+    final Set<String> ids = {};
+    for (final log in _logs) {
+      final String studentId = log['student_id']?.toString() ?? '';
+      if (studentId.isNotEmpty) ids.add(studentId);
+    }
+    return ids;
+  }
+
   /// ⏰ 태깅 시간과 지정된 자습실 출석시간을 비교해 'NONE' / 'PENDING' / 'COMPLETE'를 반환한다.
   /// - NONE: 아직 태깅 안 함
   /// - PENDING: 태깅은 했지만 지정된 출석시간 이전이라 아직 "출석 완료"로 안 침
@@ -406,6 +417,7 @@ class _TeacherAttendancePageState extends State<TeacherAttendancePage> {
 
   List<Map<String, dynamic>> get _combinedStudentStatus {
     final checkIns = _todaysCheckInsByStudentId;
+    final everCheckedIn = _everCheckedInStudentIds;
     return _roster.map((u) {
       final String id = u['id']?.toString() ?? '';
       final checkIn = checkIns[id];
@@ -419,6 +431,7 @@ class _TeacherAttendancePageState extends State<TeacherAttendancePage> {
         'checkInTime': checkIn?['time'],
         'attendanceStatus': attendanceStatus,
         'isAttendanceComplete': attendanceStatus == 'COMPLETE',
+        'hasEverCheckedIn': everCheckedIn.contains(id),
         'hasActiveViolation': violation != null,
         'violationPocket': violation?['pocket_number'],
         'violationTime': violation?['time'],
@@ -608,7 +621,9 @@ class _TeacherAttendancePageState extends State<TeacherAttendancePage> {
                                               ? '학번: ${student['studentId']} | ⏳ 출석 미완료 (제출: ${student['checkInTime']})'
                                               : (isComplete
                                                   ? '학번: ${student['studentId']} | 제출시간: ${student['checkInTime']}'
-                                                  : '학번: ${student['studentId']} | 미제출')),
+                                                  : (student['hasEverCheckedIn'] == true
+                                                      ? '학번: ${student['studentId']} | 미제출'
+                                                      : '학번: ${student['studentId']} | 미등록'))),
                                       style: TextStyle(
                                         color: hasViolation
                                             ? Colors.red[700]
@@ -809,7 +824,9 @@ class _TeacherAttendancePageState extends State<TeacherAttendancePage> {
                                               ? '⏳ 출석 미완료 (제출: ${student['checkInTime']})'
                                               : (isComplete
                                                   ? '${student['checkInTime']}'
-                                                  : '미제출')),
+                                                  : (student['hasEverCheckedIn'] == true
+                                                      ? '미제출'
+                                                      : '미등록'))),
                                       style: TextStyle(
                                         color: hasViolation
                                             ? Colors.red[700]