diff --git a/dao/print_dao.go b/dao/print_dao.go
index 4ba86f9..e4d504d 100644
--- a/dao/print_dao.go
+++ b/dao/print_dao.go
@@ -94,6 +94,9 @@ func GetPrintIsUse(printNo string) (bool, string, error) {
 	if err := globals.GetDB().Select(&result, sql, param...); err != nil {
 		return false, "", err
 	}
+	if len(result) != 1 {
+		return false, "", errors.New("打印机不存在")
+	}
 	return len(result) == 1, result[0].PrintKey, nil
 }