A power amplifier module includes a power amplifier including an amplifying unit including an amplifying transistor configured to amplify an input signal and output an output signal, and a bias unit including a bias transistor configured to provide a bias current to the amplifying transistor, and a sub bias transistor configured to provide a sub bias current to the amplifying transistor; and a control unit configured to provide a control current to the bias transistor and the sub bias transistor. The control unit is further configured to vary the control current according to the sub bias current, and a level of the sub bias current is lower than a level of the bias current.