diff --git a/object.go b/object.go
index 901e2be..8879dc6 100644
--- a/object.go
+++ b/object.go
@@ -169,7 +169,7 @@ func (s *ObjectService) Head(ctx context.Context, name string, opt *ObjectHeadOp
 		optHeader: opt,
 	}
 	resp, err := s.client.send(ctx, &sendOpt)
-	if resp.Header["X-Cos-Object-Type"][0] == "appendable" {
+	if (resp.Header["X-Cos-Object-Type"] != nil && resp.Header["X-Cos-Object-Type"][0] == "appendable") {
 		resp.Header.Add("x-cos-next-append-position",resp.Header["Content-Length"][0])
 	}