In this paper, a method for ground moving target imaging and parameter estimation suitable for frequency modulated continuous wave (FMCW) synthetic aperture radar (SAR) is studied. Firstly, the echo model of moving target under the FMCW SAR system is established. By Doppler shift compensation and time-frequency substitution, a method based on the second-order Keystone transform is proposed to correct the range cell curve of moving target. Secondly, the Hough transform is used to estimate the range velocity of moving target, and the range walk correction is carried out accordingly. Finally, the Wigner-Hough transform is utilized to estimate the Doppler frequency rate of moving target, and compensated the quadratic and cubic Doppler phases, thus achieved accurate focusing of the moving target. The simulation results show that the proposed method has high accuracy in parameter estimation, and the estimated parameters have a good focusing effect on moving target imaging.