diff --git a/relaxng.c b/relaxng.c
index 04cb55ec..c4c26cb0 100644
--- a/relaxng.c
+++ b/relaxng.c
@@ -6839,6 +6839,7 @@ xmlRelaxNGNewDocParserCtxt(xmlDocPtr doc)
         (xmlRelaxNGParserCtxtPtr) xmlMalloc(sizeof(xmlRelaxNGParserCtxt));
     if (ret == NULL) {
         xmlRngPErrMemory(NULL, "building parser\n");
+        xmlFreeDoc(copy);
         return (NULL);
     }
     memset(ret, 0, sizeof(xmlRelaxNGParserCtxt));