An impedance control apparatus and method for portable mobile communication terminal is disclosed capable of accurately adjusting impedances relative to environment when the portable mobile communication terminal is being used, wherein an impedance of a first variable impedance matching part is varied to receive a reception impedance correction signal transmitted by a base station and to detect a reception strength, an impedance of the first variable impedance matching part is set by a impedance value of the largest reception strength out of the reception strengths, the portable mobile communication terminal varies the impedance of a second variable impedance matching part to transmit a transmission impedance correction signal to a base station and to allow the base station to detect the reception strength, and the impedance setting of the second variable impedance matching part is performed using the reception strength detected by the base station.