Abstract:An MS7.0 earthquake struck Jiuzhaigou,Sichuan province on 8 August 2017.This work ob-tained two LOS co-seismic measurements by carrying out the"Two-pass"differential interferometry on two tracks(1 ascending and 1 descending)of ERS sentinel-1A images firstly;Then the co-seismic dis-placements located in near and far field were subsampled with Quad-tree sampling and uniform sampling methods,respectively.The fault slip distributions were built based on the rectangular dislocation model in an elastic half space from the subsampled measurements.The results show that:① the both inteferograms display a similar butterfly shape caused by Jiuzhaigou earthquake,with the max amplitude of -20.3 cm and 11.3 cm,respectively.② The seismogenic fault is dominated by left-lateral strike with little normal faulting,with strike of 154°and dip of 82°.③ The fault slip is mainly happened in the depth between 2 km and 15 km,with maximum slip of 0.68 m located at 9km depth,and the average rake of -22°.The mo-ments released by the earthquake is about 9.6×1018Nm(MW6.6),which is almost consistent with the seismology research.