A predistortion linearizer has signal dividing circuit dividing an input signal into two signals; signal adjusting circuit using one of the divided signals to execute predetermined adjustment and outputting a signal based on the adjustment; distortion signal generating circuit generating a distortion signal using the signal output from the signal adjusting circuit; signal synthesizing circuit synthesizing the other of the divided signals with the generated distortion signal; and signal amplifying circuit amplifying the synthesized signal and outputting an output signal, and wherein the signal adjusting circuit executes the predetermined adjustment such that there is a predetermined relationship between the level of a difference between the signal amplitudes of predetermined frequency components contained in a distortion signal and the level of a difference between the signal amplitudes of the predetermined frequency components contained in a distortion signal.