The present invention discloses an interactive method for a WLAN UE accessing a new operation network, which comprises: when the WLAN UE which has accessed a first Visited Mobile Communication Network needs to re-select a second Visited Mobile Communication Network to access, the WLAN UE sending authentication information to a Home Network of the WLAN UE through a WLAN Access Network and the second Visited Mobile Communication Network; after receiving the authentication information, the Home Network of the WLAN UE authenticate the WLAN UE according to the authentication information via the second Visited Mobile Communication Network, and sending an access instruction to the WLAN Access Network through the second Visited Mobile Communication Network; and on receiving the access instruction, the WLAN UE accesses the second Visited Mobile Communication Network via the WLAN Access Network. The method enables a WLAN UE to reselect another Visited Mobile Communication Network after accessing a Visited Mobile Communication Network.