diff --git a/conf/app.conf b/conf/app.conf
index 478482e..13a3ddc 100644
--- a/conf/app.conf
+++ b/conf/app.conf
@@ -34,6 +34,7 @@ cookie.httponly=false
 cookie.prefix=LEANOTE
 cookie.domain= # for share cookie with sub-domain
 cookie.secure=false
+session.expires=3h # 3 hour. Valid time units are "ns", "us" (or "µs"), "ms", "s", "m", "h".
 format.date=2006-01-02
 format.datetime=2006-01-02 15:04:05 # 必须这样配置
 results.chunked=false