diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c
index f5e3a736e5..6e96107498 100644
--- a/libavformat/mxfdec.c
+++ b/libavformat/mxfdec.c
@@ -2590,7 +2590,7 @@ static int64_t mxf_timestamp_to_int64(uint64_t timestamp)
 
 #define SET_TS_METADATA(pb, name, var, str) do { \
     var = avio_rb64(pb); \
-    if ((ret = avpriv_dict_set_timestamp(&s->metadata, name, mxf_timestamp_to_int64(var))) < 0) \
+    if (var && (ret = avpriv_dict_set_timestamp(&s->metadata, name, mxf_timestamp_to_int64(var))) < 0) \
         return ret; \
 } while (0)