diff --git a/business/jxutils/jxutils.go b/business/jxutils/jxutils.go
index 65f23bdc7..02d8816ae 100644
--- a/business/jxutils/jxutils.go
+++ b/business/jxutils/jxutils.go
@@ -417,7 +417,7 @@ func CalUpcCheckSum(upc12 int64) (checkSum int) {
 		sum[i%2] += int((upc12 / base) % 10)
 	}
 	sum[0] *= 3
-	return (10 - (sum[0]+sum[1])%10)
+	return (10 - (sum[0]+sum[1])%10) % 10
 }
 
 func IsUpcValid(upc string) bool {