In this paper, 1 434 earthquakes of the Maduo M_S .4 earthquake sequence on May 22, 2021 were relocated using the double-difference location method, and the focal mechanism solutions of M≥ 4.5 earthquakes were also obtained by TDMT inversion method. Through a comprehensive analysis, following conclusions were obtained: (1) The overall trend of the Maduo earthquake sequence is NWW-SEE, which is consistent with the orientation of Kunlun Pass-Jiangcuo fault. There is a NW-trending band on the northwest side of the main shock, and a sparse segment of aftershocks and a distribution zone across the Maduo-Gande fault on the southeast side, which may be caused by the difference of underground velocity structure. (2) The seismic sequence is mainly left-lateral strike-slip type, with the dominant direction of NWW, NE tendency, and high dip angle. Combined with the aftershock positioning results, it is inferred that the Kunlun Pass-Jiangcuo fault is the seismogenic fault of this earthquake. (3) The average azimuth of P axis near the main shock is 237°; the average dip angles of P axis and T axis are 15° and 16°, respectively; the average dip angle of N axis is 65°. Combined with the structural characteristics of the study area, it is inferred that the earthquake is caused by the left-lateral strike-slip dislocation of the NWW-SEE trending fault driven by the NEE-SWW horizontal compressive stress.