To provide a media gateway device that can eliminate partition loss of internal resources of an MGW and effectively utilize the internal resources of the MGW. When starting or restarting service of an MGW, a call control management part of the MGW sends a service registration request signal to MGCs. The MGCs that receive the service registration request signal send back a service registration request response signal as a response. The call control management part registers an MGC from which a response was normally received as an object for implementation of call processing. Upon reception of a service registration request response signal from at least one MGC, the call control management part enters an in-service state. The call control management part periodically performs resending of service registration request signals only to MGCs from which a response can not be normally received.