In a Push-To-Talk (PTT) communication method, during a PTT conversation between multiple mobile terminals in a PTT chat-room, a first mobile terminal specifies a second mobile terminal as a target for a forced leave and makes a request to a PTT server for a forced leave of the second mobile terminal. The PTT server forces the second mobile terminal to leave the PTT chat-room. During a PTT chat-room conversation, a disruptive member can be forced to leave the PTT chat room and is not allowed to later re-join the PTT chat room. Thus, it is possible to more smoothly run a PTT chat room in a manner fitting for the purpose, enhancing user convenience.