An authentication method and apparatus for an electronic device. A first electronic device transmits a mutual authentication request for the first electronic device and a second electronic device communication-connected with the first electronic device to an authentication server. The first electronic device receives mutual authentication information for each of the first electronic device and the second electronic device from the authentication server, and stores the mutual authentication information in the first electronic device and the second electronic device. The first electronic device determines whether reliability of an authentication state between the first electronic device and the second electronic device is maintained. The first electronic device acquires an authentication result for a service using the second electronic device from the authentication server by using the mutual authentication information for each of the first electronic device and the second electronic device, when the reliability is maintained.