The method performed by a base station and comprises receiving, from a terminal connected to a first WLAN AP, an AP re-selection response message requesting a connection change from the first WLAN AP to a second WLAN AP; transmitting, to the second WLAN AP, an AP change request message including information relating to the association of the terminal and information relating to the connection setup of the terminal; receiving, from the second WLAN AP, an AP change response message including information indicating approval, or not, of the connection of the terminal; if the second WLAN AP has provided approval, transmitting, to the first WLAN AP, an AP change indication message indicating the connection change of the terminal; and transmitting, to the terminal, an AP re-selection command message ordering connection with the second WLAN AP.