diff --git a/sm9/sm9.go b/sm9/sm9.go
index 24e2c1e..3a373b1 100644
--- a/sm9/sm9.go
+++ b/sm9/sm9.go
@@ -473,9 +473,6 @@ func DecryptASN1(priv *EncryptPrivateKey, uid, ciphertext []byte) ([]byte, error
 	if err != nil {
 		return nil, err
 	}
-	if err != nil {
-		return nil, err
-	}
 
 	hash := sm3.New()
 	hash.Write(c2Bytes)