It is difficult to obtain the focused image by the conventional SAR imaging algorithm for ship with complicated motions like oscillating and swing. The SAR imaging model and echo characteristics of oscillating ship and swing ship are separately studied in this paper. Furtherly, a set of moving ship SAR imaging processes are proposed to improve the quality of image. This method can extract and estimate the additional Doppler parameters by smoothing pseudo WignerVille distribution (SPWVD), which can obtain the focused SAR image of oscillating ship and sway ship. Finally, the effectiveness of the method is proved by simulation experiment.