The present invention provides a method and apparatus for filling Doppler signal gaps. The method comprises steps of: storing Doppler signals before and after a gap; analyzing spectral characteristics of the Doppler signals to be filled; judging whether the Doppler signals are to be frequency compensated according to the spectral parameters; compensating the Doppler signals; and filling the gap by means of weighting and superposing the frequency compensated Doppler signals to be filled and the original Doppler signals before and after the gap based on the judging result. According to the method of the present invention, the Doppler signals before and after the gap are first subjected to frequency compensation, and then weighted and superposed with the acquired Doppler signals, thus obtaining a continuous spectrogram and audio output and maintaining the original spectral characteristics of the Doppler signal.