A base station apparatus including a plurality of communication units which communicate through a different plurality of communication channels with an upper layer apparatus of the base station apparatus, a base station information acquisition unit which acquires base station information relating to the state of the base station apparatus, a channel selection unit which selects any of the plurality of communication channels in accordance with base station information, and a channel switching unit which dynamically switches the channel which is used for transmission of traffic of the mobile station apparatus to a channel which is selected by the channel selection unit.