diff --git a/builtin/cat-file.c b/builtin/cat-file.c
index 989eee0bb4..fa7bd89169 100644
--- a/builtin/cat-file.c
+++ b/builtin/cat-file.c
@@ -893,7 +893,7 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix)
 		N_("git cat-file (-t | -s) [--allow-unknown-type] <object>"),
 		N_("git cat-file (--batch | --batch-check | --batch-command) [--batch-all-objects]\n"
 		   "             [--buffer] [--follow-symlinks] [--unordered]\n"
-		   "             [--textconv | --filters]"),
+		   "             [--textconv | --filters] [-z]"),
 		N_("git cat-file (--textconv | --filters)\n"
 		   "             [<rev>:<path|tree-ish> | --path=<path|tree-ish> <rev>]"),
 		NULL