diff --git a/api/internal/adminstore/backflow.go b/api/internal/adminstore/backflow.go
index a6fcbcb..ccac9a2 100644
--- a/api/internal/adminstore/backflow.go
+++ b/api/internal/adminstore/backflow.go
@@ -6,6 +6,7 @@ import (
 	"errors"
 	"strings"
 
+	"github.com/baicai2026-baicai/goods/api/internal/gtin"
 	"github.com/jackc/pgx/v5"
 )
 
@@ -76,8 +77,20 @@ func (s *Store) CreateBackflowSubmissions(ctx context.Context, items []Submissio
 			if g == "" {
 				in.GTIN = nil
 			} else {
-				in.GTIN = &g
-				res.GTIN = &g
+				// Validate/normalize so a malformed barcode is reported as an
+				// invalid item instead of aborting the batch (the gtin column
+				// is varchar(14) and only GS1 codes are archived).
+				norm, err := gtin.Normalize(g)
+				if err != nil {
+					res.GTIN = &g
+					res.Status = "invalid"
+					res.Reason = err.Error()
+					sum.Invalid++
+					sum.Results = append(sum.Results, res)
+					continue
+				}
+				in.GTIN = &norm
+				res.GTIN = &norm
 			}
 		}