A PT (Push-To) service among SIP based session services, and particularly, a method and terminal for establishing a PT session in order to allow a certain user to use a PT box service under control of a PT server in a SIP (Session Initiation Protocol) based service, are discussed. According to an embodiment, the method of providing a Push-To (PT) box service, includes storing, in a PT server, PT box setting information of a terminal; receiving, by the PT server, a session invitation directed to the terminal; and determining, by the PT server, a routing of the session invitation to a PT box for the terminal based on at least the PT box setting information.