Abstract: Based on the meteorological observation data of maximum temperature, minimum temperature, precipitation, ralative humidity and sunshine hours in Guizhou Province from 1971 to 2020, according to the discrimination method of low temperature and rainy weather, the regional low temperature and rainy weather processes in Guizhou in the past 50 years were statistically analyzed. The spatial and temporal evolution caharcateristics and causes were analyzed by EOF and wavelet analysis. The results show that in the past 50 years, the regional low-temperature and rainy weather processes mainly occurred in the northwest of Guizhou Province, and the frequency decreased from the west to east, and decreased from the central line to the north and south sides, with the average influence area accounting for 53.8% of the whole province. In terms of time, it had obvious cycle change characteristics of 3a, 4a and 10a. The annual average occurrence times of low temperature and overcast rain processes in Guizhou region were 5, the average duration was 7d, and the longest duration was 51 days. The regional low temperature and overcast rain processes lasting less than 10 days were frequent, accounting for 72.6%. There was no obvious interdecadal difference in the beginning and end dates of the processes. The abnormal years of regional low temperature and overcast rain had a significant relationship with the 500 hPa height field and wind field in Northern Hemisphere. Among them, the geopotential height was abnormally high ( low ) in the vast area of the northern hemisphere extending from the Mediterranean Sea to the Baltic Sea in the south, from Ireland to the Black Sea in the east, most of Russia, and the Great Lakes to the Mid-Atlantic Ridge, and the number of low temperature and rainy days in Guizhou was significantly more ( less ).