An audio signal processing method is disclosed. The method comprises: providing an input audio signal comprising a plurality of input data frames offset from each other by a predetermined frame shift and each input data frame having a predetermined frame length; performing first windowing process on the plurality of input data frames in sequence with a first window function; performing predetermined signal processing on the input audio signal after the first windowing processing, and generating an output audio signal; wherein the output audio signal has a plurality of output data frames each having the predetermined frame length corresponding to the plurality of input data frames of the input audio signal; performing second windowing processing on the plurality of output data frames in sequence with a second window function; and outputting the plurality of output data frames after the second windowing processing by superimposing the plurality of output data frames with the predetermined frame shift.