diff --git a/bin/tests/dst/t_dst.c b/bin/tests/dst/t_dst.c
index 8547aa44d1..32595b1fdb 100644
--- a/bin/tests/dst/t_dst.c
+++ b/bin/tests/dst/t_dst.c
@@ -381,7 +381,8 @@ io(dns_name_t *name, isc_uint16_t id, isc_uint16_t alg, int type,
 	cleandir(tmp);
 
  failure:
-	dst_key_free(&key);
+	if (key != NULL)
+		dst_key_free(&key);
 }
 
 static void