1) Stop the listener on a regular basis then you can simply rename the file at the OS level, then on next listener startup, a new one will be created.
OR
2) If you have a 24X7 environment and the listener can not be stopped, then you can use the following steps to rename / move the file without having to restart it:
LSNRCTL>
LSNRCTL> set current_listener <listenername>
LSNRCTL> set log_status off
In another window rename the log file. Then return to previous window
LSNRCTL> set log_status on
which will create a new and empty listener.log file which will continue logging.
OR
3) Follow the document here:
Note 135063.1 How To Change the Listener Log Filename Without Stopping the Listener
原文：http://www.cnblogs.com/dfzzqq/p/6604536.html