diff --git a/ledis/cmd_kv.go b/ledis/cmd_kv.go
index 754fb95..877b5b5 100644
--- a/ledis/cmd_kv.go
+++ b/ledis/cmd_kv.go
@@ -137,7 +137,7 @@ func decrbyCommand(c *client) error {
 		return err
 	}
 
-	if n, err := c.db.DecrBy(c.args[0], -delta); err != nil {
+	if n, err := c.db.DecrBy(c.args[0], delta); err != nil {
 		return err
 	} else {
 		c.writeInteger(n)
diff --git a/ledis/t_kv.go b/ledis/t_kv.go
index bf273fb..b4c27f9 100644
--- a/ledis/t_kv.go
+++ b/ledis/t_kv.go
@@ -51,7 +51,7 @@ func (db *DB) Decr(key []byte) (int64, error) {
 }
 
 func (db *DB) DecrBy(key []byte, decrement int64) (int64, error) {
-	return db.incr(key, decrement)
+	return db.incr(key, -decrement)
 }
 
 func (db *DB) Del(keys [][]byte) (int64, error) {