Abstract: Under high resolution condition, the effect of coupling between satellite curved orbit and attitude measurement error on imaging quality was studied. Firstly, combined with imaging characteristic of high resolution spaceborne sliding spotlight synthetic aperture radar (SAR), the space-time-frequency property of echo signal was analyzed and attitude measurement error effect on it was discussed. Mapping relationship between attitude measurement error and imaging quality was also given. Then based on three-step focusing algorithm combined with high-order phase compensation procedure, the high-order compensating phase error was analyzed. The critical value of error was brought forward as to whether or not to employ high-order phase compensation could get better imaging quality. Finally, computer simulation results identify the validity of theoretical analysis.