diff --git a/backend/app/api/v1/endpoints/webhooks.py b/backend/app/api/v1/endpoints/webhooks.py
index b60a76e..6fa4f6a 100644
--- a/backend/app/api/v1/endpoints/webhooks.py
+++ b/backend/app/api/v1/endpoints/webhooks.py
@@ -46,13 +46,16 @@ async def mom_inbound_webhook(
     if not settings.TRACK_WEBHOOK_KEY or x_api_key != settings.TRACK_WEBHOOK_KEY:
         raise HTTPException(status_code=401, detail="Unauthorized: invalid X-API-Key")
 
-    # ── 按 serial_number（优先）或 sku 匹配"当前位于仓库"的产品 ──
+    # ── 按 serial_number / external_serial（双字段联合）或 sku 匹配"当前位于仓库"的产品 ──
     product = None
     if payload.serial_number:
         product = (
             await db.execute(
                 select(Product).where(
-                    Product.serial_number == payload.serial_number,
+                    or_(
+                        Product.serial_number == payload.serial_number,
+                        Product.external_serial == payload.serial_number,
+                    ),
                     Product.current_location_id == "virtual_warehouse",
                 )
             )
@@ -151,7 +154,10 @@ async def mom_outbound_webhook(
         product = (
             await db.execute(
                 select(Product).where(
-                    Product.serial_number == payload.serial_number,
+                    or_(
+                        Product.serial_number == payload.serial_number,
+                        Product.external_serial == payload.serial_number,
+                    ),
                     where_cond,
                 )
             )