A de-bounce circuit is disclosed. The de-bounce circuit comprises a wave-shaping circuit, a filtering circuit and a trigger circuit. The wave-shaping circuit is adapted to shape a control signal and output a wave-shaping signal. The control signal may be generated from a mechanical switch. The filtering circuit charges/discharges a capacitor according to the wave-shaping signal, and determines whether to generate a judgment signal according to a voltage of the capacitor. The trigger circuit determines whether to generate an enable signal according to the number of times of the judgment signal.