Abstract: Compared with traditional monostatic SAR, Bistatic synthetic aperture radar has the advantages of obtaining richer information, anti-electronic jamming, anti-destroy, anti-intercept. So,it has broader application prospect. However, bistatic SAR system is confronted with the space, time and frequency synchronization and other technical problems. It is very difficult to obtain the actual bistatic SAR echo data. So, a fast echo simulation algorithm based on two-dimensional principle of stationary phase (2D-PSP) and inverse processing of RD imaging algorithm was proposed in this paper. A fast echo data simulation for bistatic SAR was achieved. Comparing to distance time-domain overlay algorithm and one-dimensional FFT algorithm, this algorithm's simulating speed has a significant improvement and it can be uesd on shift-variant mode.The simulation results of a point target and natural scene verify the effectiveness of the algorithm. The test result of simulating speed can verify high efficiency of the algorithm.