diff --git a/lib/vquic/ngtcp2.c b/lib/vquic/ngtcp2.c
index 107fcb8c17..3374e9eebd 100644
--- a/lib/vquic/ngtcp2.c
+++ b/lib/vquic/ngtcp2.c
@@ -1676,6 +1676,12 @@ static ssize_t ngh3_stream_send(struct Curl_easy *data,
     return -1;
   }
 
+  /* Reset post upload buffer after resumed. */
+  if(stream->upload_mem) {
+    stream->upload_mem = NULL;
+    stream->upload_len = 0;
+  }
+
   *curlcode = CURLE_OK;
   return sent;
 }