The invention discloses a method for selecting an inverse synthetic aperture radar ship imaging time window, and belongs to the technical field of radars. According to the method, theoretical analysisand numerical simulation verify that the instantaneous Doppler frequency of a scattering point approximately meets a change rule of a linear frequency modulation signal only within a short time, a computational formula for the length of a short time period is deduced, a parameter estimation method combining data extrapolation and compressed sensing is designed for estimation of the frequency modulation slope and the center frequency of the short-time linear frequency modulation signal, the instantaneous Doppler frequency changes of the main strong scattering points in the complete data acquisition time are obtained through data correlation of adjacent short time periods, the information is integrated, and the time period with relatively stable instantaneous Doppler frequency changes of the strong scattering points is selected. According to the method disclosed by the invention, the effectiveness of the proposed method is verified according to the processing results of the simulation and the measured data, and through comparison with a method based on an image contrast based algorithm (ICBA), the method disclosed by the invention has an advantage that the better imaging quality isobtained.