The present invention provides a technique capable of processing to automatically and optimally select types of external networks and a communication system, and at the same time, capable of switching network selection upon a user's arbitrary opportunity. A communication connection device 1 is provided with: a network communication adaptor 13 connecting a terminal device 4; external network communication adaptors 11, 12 compatible with external networks; a network selection processing portion 102 automatically selecting a network from the external networks according to profile information 141 previously including at least one of types of networks and a communication system; re-selection processing instruction mechanisms 15, 103 designed to cause, as a result of a user's operation, the network selection processing portion 102 to start selection processing.