Abstract: A new algorithm for Doppler frequency compensation used in stepped-frequency signal processing is proposed.Doppler frequency compensation can be worked out quickly and accurately according to the distance-velocity information included in time-frequency data matrix,and the main clutter's features of different distance cells that it has almost the same Doppler frequency and occupies several distance cells.The fast algorithm of digital signal processing such as FFT is adopted.The experiment showed that the method is simple and effective,and has been applied in the signal processing system of millimeter wave fire-control radars.