A method for eliminating sound is disclosed. The method is applied to an electronic device capable of connecting with a sound playback device and includes a microphone. The method includes the following steps of: receiving a first input sound via the microphone to acquire a first input sound signal; recording the first input sound signal and transmitting the first input sound signal to the sound playback device; receiving a second input sound from the sound playback device to acquire a second input sound signal, wherein the second input sound is generated by the sound playback device according to the first input sound signal; determining a difference in generation times between the first input sound signal and the second input sound signal; and filtering the second input sound signal according to the difference in generation times and the first input sound signal.