diff --git a/Assets/Editor/Window/AnimationClipGeneratorCore.cs b/Assets/Editor/Window/AnimationClipGeneratorCore.cs
index d566e85d1..9776a6e26 100644
--- a/Assets/Editor/Window/AnimationClipGeneratorCore.cs
+++ b/Assets/Editor/Window/AnimationClipGeneratorCore.cs
@@ -533,6 +533,16 @@ namespace AibisDream.SystemEditor
             settings.loopTime = animationData.loop;
             AnimationUtility.SetAnimationClipSettings(clip, settings);
 
+            // 强制更新动画长度 (m_StopTime) - 修复复用已有 clip 时长度未更新的问题
+            float totalDuration = keyframes.Count > 0 ? keyframes[keyframes.Count - 1].time : 0f;
+            SerializedObject serializedClip = new SerializedObject(clip);
+            SerializedProperty stopTimeProp = serializedClip.FindProperty("m_StopTime");
+            if (stopTimeProp != null)
+            {
+                stopTimeProp.floatValue = totalDuration;
+                serializedClip.ApplyModifiedProperties();
+            }
+
             // 保存 / 更新 AnimationClip 资源
             if (isNewClip)
             {