diff --git a/gst/gstevent.c b/gst/gstevent.c
index 825feca8cd..bf9b59fa77 100644
--- a/gst/gstevent.c
+++ b/gst/gstevent.c
@@ -448,6 +448,7 @@ void
 gst_event_set_seqnum (GstEvent * event, guint32 seqnum)
 {
   g_return_if_fail (GST_IS_EVENT (event));
+  g_return_if_fail (seqnum != GST_SEQNUM_INVALID);
 
   GST_EVENT_SEQNUM (event) = seqnum;
 }