diff --git a/errors.go b/errors.go
index 08755083..a559aaa6 100644
--- a/errors.go
+++ b/errors.go
@@ -31,4 +31,6 @@ var (
 	ErrEmptySlice = errors.New("empty slice found")
 	// ErrDryRunModeUnsupported dry run mode unsupported
 	ErrDryRunModeUnsupported = errors.New("dry run mode unsupported")
+	// ErrInvaildDB invalid db
+	ErrInvaildDB = errors.New("invalid db")
 )
diff --git a/gorm.go b/gorm.go
index f11fb9e1..0eb377e9 100644
--- a/gorm.go
+++ b/gorm.go
@@ -3,7 +3,6 @@ package gorm
 import (
 	"context"
 	"database/sql"
-	"errors"
 	"fmt"
 	"sync"
 	"time"
@@ -331,7 +330,7 @@ func (db *DB) DB() (*sql.DB, error) {
 		return sqldb, nil
 	}
 
-	return nil, errors.New("invalid db")
+	return nil, ErrInvaildDB
 }
 
 func (db *DB) getInstance() *DB {