Abstract: On many application occasions, especially on Missile-borne platform, the SAR imaging in great squint angle mode is very demanding of the simultaneousness and complexity of the algorithm. An advanced CS imaging algorithm is presented in this paper which corrects the range walk in time domain to reduce the two dimensional coupling and then corrects other parts of the range cell migration and implements focusing. The algorithm can fulfill the function of range cell migration after simple phase multiplying, with appropriate arithmetic quantum. This thesis analyzes the whole process of the algorithm in detail, and verifies the validity of this method by the simulation experiments. At last, the qualities of the SAR images in different squint angles are analyzed, and the result show that scatters in relatively greater squint angles maintain good the peak side lobe ratio (PSLR) and the integrated side lobe ratio (ISLR), but the practical resolving capability will be reduced.