Empathy chat client stores chat history in your home directory under
~/.local/share/TpLogger/logs/
You will see a directory for each account you have configured and inside each are directories for each person you have spoken to.
To delete the chat history completely simply delete the contents of ~/.local/share/TpLogger/logs . Or you can be more selective and choose which conversations you wish to remove.
To prevent Empathy from recording chat history in future, In Empathy, select Edit > Preferences from the menu. On the General Tab, untick the option " Log conversations ".
来源： http://richardjh.org/blog/clear-empathy-logs/
