Abstract: The Circular Synthetic Aperture Radar (CSAR), unlike the linear SAR, has the capability to extract three-dimensional imaging information of a target scene. In this paper, a novel CSAR wavefront reconstruction method is proposed for three-dimensional imaging. The proposed method compensates the effects of the phase components introduced by the radars trajectory to form reconstructed image, which avoids calculating the complicated Hankel function. Thus the complexity of the algorithm can be reduced. Finally, the validity of the presented method is clarified by both simulated data and experimental data sets.