A base station device includes a processing unit that performs a base station process on a mobile terminal and a core network device; a cellular communication unit for connection to the mobile terminal; and a connection control unit, wherein the cellular communication unit receives a connection request message for connection to an external network from the mobile terminal, the base station processing unit replaces an access point name of the connection request message with “APN-L” and transfers the connection request message to a mobility management entity when the access point name indicating a local network is other than APN-L, and the connection control unit performs a radio bearer setting process between the mobile terminal and the connection control unit, based on a context setup request message in which the “APN-L”, having a bearer established, received from the mobility management entity is stored.