diff --git a/relay/adaptor/openai/main.go b/relay/adaptor/openai/main.go
index 97080738..8eb3da96 100644
--- a/relay/adaptor/openai/main.go
+++ b/relay/adaptor/openai/main.go
@@ -27,6 +27,8 @@ const (
 func StreamHandler(c *gin.Context, resp *http.Response, relayMode int) (*model.ErrorWithStatusCode, string, *model.Usage) {
 	responseText := ""
 	scanner := bufio.NewScanner(resp.Body)
+	buffer := make([]byte, 256*1024)
+	scanner.Buffer(buffer, len(buffer))
 	scanner.Split(bufio.ScanLines)
 	var usage *model.Usage