The invention discloses a method for call state supporting an early-session. In the method, called side early-session playback is compatible, and the method also satisfies session media negotiation and resource reservation during the process of establishing a call. In the method, during the media negotiation, SDPs of early-session and session are integrated as a composite SDP to be sent to a callstate calling terminal; the call state calling terminal finishes the work of media negotiation, link establishment, resource reservation and the like before a called party ringing; after the called party ringing, the early-session is used as calling playback; and after the called party picks up a telephone, the session is activated to carry out session negotiation, and the call stars after the negotiation.