A peace conference was a diplomatic meeting for peace between conflicting parties.
In 2293, Camp Khitomer was the location of the Khitomer Conference, a peace conference between the United Federation of Planets and the Klingon Empire (Star Trek V: The Final Frontier)
In 2364, the neutral conference planet Parliament was the location of a peace conference between the Anticans and Selay. The USS Enterprise-D delivered Antican and Selay delegates there that year. (TNG: "Lonely Among Us")