diff --git a/src/main/java/com/aida/seller/module/listing/controller/ListingController.java b/src/main/java/com/aida/seller/module/listing/controller/ListingController.java
index a5d4df9..a96609c 100644
--- a/src/main/java/com/aida/seller/module/listing/controller/ListingController.java
+++ b/src/main/java/com/aida/seller/module/listing/controller/ListingController.java
@@ -94,4 +94,11 @@ public class ListingController {
         IPage<ListingPageVO> page = listingService.getShopListings(sellerId, designFor, pageNum, pageSize);
         return Response.success(PageResponse.success(page));
     }
+
+    @Operation(summary = "迁移旧商品水印数据", description = "为所有已发布商品中缺失水印记录的图片生成水印并写入数据库，返回处理数量")
+    @PostMapping("/migrate/watermarks")
+    public Response<Integer> migrateWatermarks() {
+        int count = listingService.migrateWatermarks();
+        return Response.success(count);
+    }
 }
diff --git a/src/main/java/com/aida/seller/module/listing/service/ListingService.java b/src/main/java/com/aida/seller/module/listing/service/ListingService.java
index b8903c9..5e8d128 100644
--- a/src/main/java/com/aida/seller/module/listing/service/ListingService.java
+++ b/src/main/java/com/aida/seller/module/listing/service/ListingService.java
@@ -82,4 +82,12 @@ public interface ListingService extends IService<ListingEntity> {
      * @return 分页商品列表
      */
     IPage<ListingPageVO> getShopListings(Long sellerId, String designFor, int pageNum, int pageSize);
+
+    /**
+     * 迁移旧商品图片的水印数据：为所有已发布商品生成缺失的水印记录并存入数据库。
+     * 仅处理尚无水印记录的原图，已存在水印记录的图片跳过。
+     *
+     * @return 迁移处理的商品数量
+     */
+    int migrateWatermarks();
 }
diff --git a/src/main/java/com/aida/seller/module/listing/service/ListingServiceImpl.java b/src/main/java/com/aida/seller/module/listing/service/ListingServiceImpl.java
index 174584e..c59f0c7 100644
--- a/src/main/java/com/aida/seller/module/listing/service/ListingServiceImpl.java
+++ b/src/main/java/com/aida/seller/module/listing/service/ListingServiceImpl.java
@@ -432,4 +432,67 @@ public class ListingServiceImpl extends ServiceImpl<ListingMapper, ListingEntity
         }
         return result;
     }
+
+    @Override
+    public int migrateWatermarks() {
+        Set<String> watermarkCategories = Set.of(
+                ImageCategoryEnum.COVER.getCode(),
+                ImageCategoryEnum.MAIN_PRODUCT.getCode(),
+                ImageCategoryEnum.PRODUCT.getCode(),
+                ImageCategoryEnum.SKETCH.getCode(),
+                ImageCategoryEnum.APPAREL.getCode());
+
+        // 查出所有已发布且未删除的商品
+        List<ListingEntity> listings = this.list(
+                new LambdaQueryWrapper<ListingEntity>()
+                        .eq(ListingEntity::getStatus, 1)
+                        .eq(ListingEntity::getDeleted, 0));
+
+        int count = 0;
+        for (ListingEntity listing : listings) {
+            Long listingId = listing.getId();
+
+            // 查出该商品已有的水印记录，构建 originalUrl -> watermarkedUrl map
+            List<ListingWatermarkImageEntity> existingWatermarks =
+                    listingWatermarkImageMapper.selectByListingId(listingId);
+            Map<String, String> existingMap = existingWatermarks.stream()
+                    .collect(Collectors.toMap(
+                            ListingWatermarkImageEntity::getOriginalUrl,
+                            ListingWatermarkImageEntity::getWatermarkedUrl,
+                            (a, b) -> a));
+
+            // 查出该商品所有需要水印的图片
+            List<ListingImageEntity> images = listingImageMapper.selectList(
+                    new LambdaQueryWrapper<ListingImageEntity>()
+                            .eq(ListingImageEntity::getListingId, listingId)
+                            .in(ListingImageEntity::getCategory, watermarkCategories));
+
+            for (ListingImageEntity img : images) {
+                String originalUrl = img.getImageUrl();
+
+                // 已有水印记录则跳过
+                if (existingMap.containsKey(originalUrl)) {
+                    continue;
+                }
+
+                // 生成水印并入库
+                String watermarkedUrl = imageWatermarkUtil.applyWatermark(originalUrl);
+                watermarkedUrl = minioUtil.convertToLogicalPath(watermarkedUrl);
+
+                ListingWatermarkImageEntity watermark = new ListingWatermarkImageEntity();
+                watermark.setListingId(listingId);
+                watermark.setCategory(img.getCategory());
+                watermark.setOriginalUrl(originalUrl);
+                watermark.setWatermarkedUrl(watermarkedUrl);
+
+                try {
+                    listingWatermarkImageMapper.insert(watermark);
+                    count++;
+                } catch (Exception ignored) {
+                    // 唯一索引冲突（并发或重复数据），忽略
+                }
+            }
+        }
+        return count;
+    }
 }