Abstract: Based on the monthly average reanalysis data from NCEP/NCAR and the daily precipitation data from 84 surface observation stations in Guizhou Province from September to November during 2010—2021, the temporal and spatial variation characteristics of rainstorm in boreal autumn were analyzed, and the relationship between the rainstorm and atmospheric circulation was investigated. The results show that: (1) In the past 10 years, the rainstorm of Guizhou mainly occurred from September to October, with the most in September, and never in November. Moreover, the frequency and duration showed a significant upward trend on the whole, with a 3-year periodic vibration. In 2020, the duration was the longest, the range was the largest and the intensity was the strongest, while in 2012, the frequency, range of influence and duration of the process were the least. (2) The frequent occurrence area of rainstorm was mainly located in the central and western of Guizhou Province, which was consistent with the distribution of accumulated precipitation, and the low value centers are mainly concentrated in the southeast and northwest Guizhou. Also, the maximum centers of the extreme rainfall were mainly distributed in the middle west and the northeastern margin. (3) Guizhou is located on the northern side of the upper South Asian High (eastern type) as well as the northwestern side of the Western Pacific Subtropical High. The central and western regions are mainly affected by the warm and moist air from the Western Pacific and the South China Sea, and the abundant water vapor is conducive to the formation of heavy rain. The rest of the area is dominated by the southeast flow from the rear of the continental high pressure, the ground is influenced by the weak cold air, which is not conducive to the formation of rainstorm.