Abstract: In order to explore the seismogenesis mechanism of the Beijing Shunyi earthquake swarm in March and April 2020, the missing earthquake detection of template matching, waveform cross-correlation phase detection, earthquake precise location, focal mechanism calculation, rupture radius and stress drop and other focal parameters were carried out. The results show that: ① The seismogenic structure of the Shunyi swarm is NW trending, and the epicenter show the migration characteristics from NW to SE. ② Except for the first M_L2.4 earthquake in the swarm that cannot be calculated, the rupture area of the other largest two M_L≥2.0 earthquakes are in the static stress loading area generated by previous earthquakes. ③ No repeating earthquakes were detected in the swarm. Combined with the mechanism model of earthquake swarm proposed by predecessors, it is analyzed that the random model can well interpreted the above results. The results of this article may provide scientific reference for seismic risk analysis in Beijing area.