Abstract: Due to the relative scarcity of cloud and precipitation physics observations in Southern Xinjiang (hereinafter referred to as “Southern Xinjiang”), there has long been a lack of scientific and objective understanding regarding the macro- and microphysical characteristics of clouds in this region. In this study, high-resolution satellite data from FY-4A, combined with precipitation data from regional automatic weather stations, hourly precipitation data from CMPAS, and ERA5 reanalysis data, are used to conduct an in-depth analysis of the atmospheric environmental conditions and cloud macro- and microphysical characteristics of a sustained heavy rainfall event that occurred in the alpine mountainous areas of Southern Xinjiang from May 28 to 31, 2022. The results indicate that this rainstorm event was characterized by a long duration, extensive spatial coverage, and distinct phased evolution, which can be specifically divided into four stages: the onset phase, the concentrated precipitation phase, the sustained precipitation phase, and the weakening and dissipation phase. The main reason for the long duration of this precipitation is the stagnation of the circulation caused by the stable maintenance of a high-pressure ridge over the Junggar Basin to the Mongolian Plateau. The heavy rainfall center is located in the convergence area of two water vapor transport belts in the west and east, and the water vapor content in the middle layer is significantly higher than that in the upper layer and the boundary layer. The precipitation in the first two stages was primarily caused by the sequential alignment, continuous movement, merging, and strengthening of small and medium-scale convective cloud clusters guided by environmental winds. In the last two stages, however, the precipitation was triggered by the synergistic effect of long-term latent heat release in the later period of sustained precipitation and topographic forced lifting, which generated local convection. The cloud top types during this persistent precipitation event included warm water clouds, supercooled water clouds, mixed clouds, and cirrus clouds.?Among them, the primary cloud type that causes precipitation are mixed clouds. Over the heavy rainfall center, the bright temperature is mainly distributed in the range of -46~-30 ℃, the cloud top height is mainly distributed between 8~10.6 km, the cloud optical thickness is mainly in the range of 20~70, and the effective radius of cloud particles is mainly distributed between 15~40 μm. The variation of bright temperature and cloud top height over time has a good correspondence with hourly precipitation.