diff --git a/br/use-br-command-line-tool.md b/br/use-br-command-line-tool.md
index c9bd3da4f16d9..2acbe3edb2117 100644
--- a/br/use-br-command-line-tool.md
+++ b/br/use-br-command-line-tool.md
@@ -47,7 +47,7 @@ A `br` command consists of multiple layers of sub-commands. Currently, br comman
 * `--cert`: specifies the path to the SSL certificate in the PEM format.
 * `--key`: specifies the path to the SSL certificate key in the PEM format.
 * `--status-addr`: specifies the listening address through which `br` provides statistics to Prometheus.
-* `--concurrency`: the number of concurrent tasks during the backup or restore.
+* `--concurrency`: the number of concurrent tasks during the backup or restore. If `--ratelimit` and `--concurrency` are set simultaneously, BR ignores `--concurrency`.
 
 ## Commands of full backup