A method for transmitting a signal from a base station transceiver system (BTS) to a base station controller (BSC) when there is no data transmitted from a mobile station while in discontinuous transmission (DTX) mode, in a mobile communication system. Upon detection of the discontinuous transmission mode, it is determined what type of frame was last transmitted from the mobile station, and the present power control information is set according to the type of frame. Thereafter, the base station transceiver system transmits a reverse message including the present power control information to the base station controller over a dedicated control channel. If there is data being transmitted between the mobile station and the base station transceiver system at the time where the discontinuous transmission mode is detected, the previous power control information is set to the present power control information.