To easily restrain leakage of a carrier power signal to a load side.

This PWM modulation device subjects an input digital signal S1 to pulse width modulation (PWM), to generate a pair of PWM power signals S7, S15 mutually in a complementary relation of 2, suppresses in the respective PWM power signals a carrier frequency component via power LPF8, 24 to obtain a pair of power signals, balance drives a load (speaker 12) by a pair of the power signals, so as to make a fixed edge side K of these PWM power signals capable of shifting at random in a time axial direction, and disperses a spectrum of respective carrier of a pair of these PWM power signals S7, S15, so that a peak level of the carrier leaking to this load side can be decreased.