diff --git a/debug-tree.c b/debug-tree.c
index 94ffd8ee..f6bd5d8b 100644
--- a/debug-tree.c
+++ b/debug-tree.c
@@ -30,7 +30,15 @@
 
 static int print_usage(void)
 {
-	fprintf(stderr, "usage: debug-tree [ -e ] device\n");
+	fprintf(stderr, "usage: btrfs-debug-tree [ -e ] [ -d ] [ -r ] [ -R ]\n");
+	fprintf(stderr, "                        [-b block_num ] device\n");
+	fprintf(stderr, "\t-e : print detailed extents info\n");
+	fprintf(stderr, "\t-d : print info of btrfs device and root tree dirs"
+                    " only\n");
+	fprintf(stderr, "\t-r : print info of roots only\n");
+	fprintf(stderr, "\t-R : print info of roots and root backups\n");
+	fprintf(stderr, "\t-b block_num : print info of the specified block"
+                    " only\n");
 	fprintf(stderr, "%s\n", BTRFS_BUILD_VERSION);
 	exit(1);
 }