diff --git a/apps/ai-game-creator-shell/src-tauri/src/game_distribution_publish.rs b/apps/ai-game-creator-shell/src-tauri/src/game_distribution_publish.rs
index 92a37e851..f8e86833f 100644
--- a/apps/ai-game-creator-shell/src-tauri/src/game_distribution_publish.rs
+++ b/apps/ai-game-creator-shell/src-tauri/src/game_distribution_publish.rs
@@ -446,6 +446,9 @@ fn metadata_digest(
     hasher.update(&bytes);
     hasher.update(price_mud_points.to_le_bytes());
     for image in media.cover.iter().chain(media.screenshots.iter()) {
+        // 逐张带长度前缀：图片之间没有分隔符，只串裸字节会让「封面 [1,2] + 截图 [3]」与
+        // 「封面 [1] + 截图 [2,3]」撞成同一摘要，本地幂等账本就会把改过的图当成重放。
+        hasher.update((image.bytes.len() as u64).to_le_bytes());
         hasher.update(&image.bytes);
     }
     Ok(format!("{:x}", hasher.finalize()))
@@ -1672,6 +1675,31 @@ mod tests {
             metadata_digest(&metadata, 0, &media).expect("changed"),
             first
         );
+        // 分片边界也要进摘要：两组图裸字节串起来相同，但封面/截图的切分不同。
+        let split_a = PublishMedia {
+            cover: Some(DraftImage {
+                bytes: vec![1, 2],
+                content_type: "image/png",
+            }),
+            screenshots: vec![DraftImage {
+                bytes: vec![3],
+                content_type: "image/png",
+            }],
+        };
+        let split_b = PublishMedia {
+            cover: Some(DraftImage {
+                bytes: vec![1],
+                content_type: "image/png",
+            }),
+            screenshots: vec![DraftImage {
+                bytes: vec![2, 3],
+                content_type: "image/png",
+            }],
+        };
+        assert_ne!(
+            metadata_digest(&metadata, 0, &split_a).expect("split a"),
+            metadata_digest(&metadata, 0, &split_b).expect("split b")
+        );
     }
 
     #[test]