diff --git a/bill_man.service b/bill_man.service
index c7a4135..840ed08 100644
--- a/bill_man.service
+++ b/bill_man.service
@@ -16,6 +16,7 @@ Type=forking
 PrivateDevices=yes
 PrivateTmp=yes
 ProtectSystem=full
+ReadOnlyDirectories=/home/admin/service/bill_man
 ReadWriteDirectories=/home/admin/service/bill_man/log
 ProtectHome=yes
 NoNewPrivileges=yes