Abstract:An MS6.9 earthquake occurred near Menyuan County, Qinghai Province, China on January 8, 2022. The epicenter of Menyuan MS6.9 earthquake is about 33km only away from another MS6.4 earthquake near Menyuan on January 21, 2016. These two events both occurred near the Lenglongling fault zone, and the aftershocks of these two sequences were closely distributed. The focal mechanism of the 2022 Menyuan MS6.9 earthquake is strike-slip with a moment magnitude of MW6.6, while the focal mechanism of the 2016 Menyuan MS6.4 earthquake is thrust with a moment magnitude of MW5.9. It is of great significance to compare the characteristics of these two earthquake sequences to have a better understanding of the aftershock attenuation and other characteristics of sequences occurred near the Lenglongling fault zone and its adjacent areas. After comparing the temporal and spatial evolutional characteristics of the aftershocks of these two Menyuan earthquakes, it can be concluded that there are some differences between the source mechanism and rupture scale of these two events. As to the former one, the rupture of the seismogenic fault is much more sufficient. As a result, the energy released by this event is stronger and the seismicity of its aftershock is much more active. While to the latter one, the seismogenic fault failed to rupture to the surface, and the seismicity of its aftershocks is less intense. We also find that the differences between 2022 Menyuan MS6.9 earthquake and 2016 Menyuan MS6.4 earthquake sequences are considered to be closely related to the rupture process of the seismogenic fault and also affected by the regional tectonic environment.