Based on daily precipitation data from 44 national meteorological stations in the southern Xinjiang and the NCEP/NCAR reanalysis data from May to September (warm season) during 1961-2020, the spatial and temporal variation characteristics of rainstorm and large-scale circulation anomalies under different decades and climatic background (warm-dry period and warm-wet period) in the southern Xinjiang were analyzed. The results show that the cumulative rainstorm days, rainstorm stations and rainstorm rainfall in the warm season of the southern Xinjiang has been increasing since 1961, but the variation trend of rainstorm intensity and the proportion of rainstorm rainfall in total precipitation was not obvious. The cumulative rainstorm days, rainstorm stations and rainstorm rainfall in the warm-wet period in the southern Xinjiang were significantly more than those in the warm-dry period, and the rainstorm intensity and the proportion of rainstorm rainfall in the total precipitation had little difference in the warm-wet period and the warm-dry period. After entering the warm-wet period, the rainstorm days and rainstorm rainfall amount increased in most stations in the southern Xinjiang (the most obvious increase was at southwest stations), but the increase extent in mountain area was smaller than that in plain. The central Asian trough, central Asian vortex and Tarim easterly low level jet were the main influencing systems for the heavy rain in the warm season in the southern Xinjiang. The heavy rain in the warm season in the southern Xinjiang was dominated by low vortex type in the warm-dry periods, and low trough type in the warm-wet periods. The easterly flow 850 hPa extended westward more obviously in the low vortex rainstorm than in the low trough rainstorm. In the circulation difference field between the warm-wet periods and the warm-dry period, the circulation anomaly in the high latitude area of the low trough rainstorm and the low vortex rainstorm showed reverse change characteristics.