diff --git a/tests/unit/test_clip_operations.py b/tests/unit/test_clip_operations.py
index 2c78fceaf..d93115692 100755
--- a/tests/unit/test_clip_operations.py
+++ b/tests/unit/test_clip_operations.py
@@ -12,7 +12,7 @@
 from __future__ import annotations
 
 import unittest
-from dataclasses import dataclass
+from dataclasses import FrozenInstanceError, dataclass
 
 from packages.domain.clip_operations import (
     ROUND_PRECISION,
@@ -166,7 +166,7 @@ class TestCalculateSplit(unittest.TestCase):
     def test_frozen_result(self):
         """SplitResult 是 frozen dataclass。"""
         result = calculate_split(duration=5.0, split_time=2.0)
-        with self.assertRaises(Exception):
+        with self.assertRaises(FrozenInstanceError):
             result.left_duration = 3.0  # type: ignore[misc]
 
 
@@ -410,7 +410,7 @@ class TestCalculateMerge(unittest.TestCase):
             _MockClip(id="c2", order=1, duration=3.0),
         ]
         result = calculate_merge(clips)
-        with self.assertRaises(Exception):
+        with self.assertRaises(FrozenInstanceError):
             result.total_duration = 10.0  # type: ignore[misc]