An adaptive feedback estimation and cancellation (AFEC) apparatus includes: a controller for generating and outputting control information by using a synchronization signal from an external synchronization acquisition unit and base station information, in order to remove a feedback signal that exists in a forward/reverse repeater signal to be repeated and then send the forward/reverse repeater signal; a first feedback prediction canceller for adaptively removing a feedback signal that exists in the forward repeater signal based on the control information from the controller and automatically adjusting the gain of the forward repeater signal; and a second feedback prediction canceller for adaptively removing a feedback signal that exists in the reverse repeater signal based on the control information from the controller and automatically controlling the gain of the reverse repeater signal.