Abstract: Aiming at both the motion error limits airborne SAR resolution seriously and the application of lower carry-frequency radars,a kind of time-domain compensation algorithm for airborne wide-beam SAR motion errors is put forward.Based on the research of which the azimuth residual motion error varies with the azimuth position after compensating two-step motion,the algorithm implements motion error compensation for every divisional data-block in time-domain after the SAR data are divided into many small-blocks in frequency-domain,thus overcoming the limitation of the motion error form,and high-resolution SAR images are obtained.The realizing steps of this method is given,and simulation experimentation and real SAR data imaging results are given to prove the feasibility of the algorithm.