Method and system for avoiding narrowing of terminal capability after controlled switching

The invention discloses a method and a system for avoiding narrowing of terminal capability after controlled switching. In a process of controlled switching of a terminal between WiMax base stations, in a switching preparation state, a handover request (HO-REQ) sent to a group of target base stations by a source service base station carries capability parameters acquired through negotiation between the source service base station and the terminal and the capability parameters of the terminal; after receiving the HO-REQ, each target base station in the group of target base stations negotiates capability according to the capability parameters of the terminal and the capability parameters of the target base station and records the new capability parameters acquired through negotiation; and in a switching implementation stage, the terminal selects one target base station from the group of target base stations to access and the target base station notifies the terminal the new capability parameters acquired through negotiation. By the method and through the system, the narrowing of the capability caused by controlled switching of the terminal is avoided.