Small earthquake data from the Pishan M_S6.5 aftershocks are collected by the Xinjiang Regional Digital Seismic Observation Network. Five parameters of the focal region are obtained by micro genetic inversion:stress drop of 75.95bars,quality factor parameters Q₀ of 186.33 and η of 0.26,geometric attenuation parameters R₁ of 72.18km and R₂ of 139.70km. We calculate the Fourier spectrum and combine with random phase spectrum to get the ground motion time history,and build the strong motion acceleration attenuation relationship. The strong ground motion acceleration attenuation of Pishan area is obtained. Because of the lack of strong ground motion records,we join the records of Wuqia earthquake on October 5,2008,the Aketao earthquake on October 6,2008 and the Lop earthquake on March 9,2012. The comparison of the calculation results and the empirical attenuation relationships with strong ground motion records reveals that the strong motion data of Pishan and Lop earthquake are higher than the empirical attenuation relationships. The Wuqia earthquake strong motion data are consistent with Yu Yanxiang(2013) short axis result,and lower than the present result.