diff --git a/src/emqx_alarm.erl b/src/emqx_alarm.erl
index 62ce1af8b..53cd9561d 100644
--- a/src/emqx_alarm.erl
+++ b/src/emqx_alarm.erl
@@ -375,6 +375,8 @@ normalize_message(high_cpu_usage, #{usage := Usage}) ->
     list_to_binary(io_lib:format("~p% cpu usage", [Usage]));
 normalize_message(too_many_processes, #{usage := Usage}) ->
     list_to_binary(io_lib:format("~p% process usage", [Usage]));
+normalize_message(license_usage, #{high_watermark := High}) ->
+    iolist_to_binary(["License: the number of connections exceeds ", High, "%"]);
 normalize_message(partition, #{occurred := Node}) ->
     list_to_binary(io_lib:format("Partition occurs at node ~s", [Node]));
 normalize_message(<<"resource", _/binary>>, #{type := Type, id := ID}) ->