diff --git a/src/main/resources/application.properties b/src/main/resources/application.properties
index c181106..c1da5a4 100644
--- a/src/main/resources/application.properties
+++ b/src/main/resources/application.properties
@@ -46,5 +46,7 @@ spring.main.allow-bean-definition-overriding=true
 # @since 2.1.0
 # 配置使用什么类型 TokenStore,支持 jdbc, jwt
 sos.token.store=jwt
+# jwt key (length >= 16), optional
+#sos.token.store.jwt.key=IH6S2dhCEMwGr7uE4fBakSuDh9SoIrRa