Using the daily average and minimum temperatures of 10 national observatories in Tongren City from 2009 to 2018, statistically analyze the 20 cold wave weather processes that occurred in the past ten years, and analyze their distribution characteristics and circulation situation to obtain: (1) nearly ten In terms of the overall spatial distribution of the annual cold wave, it mostly occurs in the southeastern area of ??Tongren City, and Wanshan Town has the most occurrences; (2) From the seasonal distribution, the cold wave occurs more frequently in winter and spring, especially in February, the peak frequency; (3 ) The path of cold air invading Tongren City from the south of the key area is divided into type Ⅰ northeast path (21%), type Ⅱ northeast path (68%), type Ⅲ northeast + northwest path (11%); cold air goes south from Henan- North Hunan invaded the east of Tongren City, including Type Ⅰ and Type II paths. In addition to the Type Ⅲ path invading the east of Tongren City from Henan-Northern Hunan, a part of it invaded the west of Tongren City from central Sichuan through northwest Guizhou. (4) The general circulation situation of the eruption of the cold wave is mainly meridian type accounted for 42%, weft type accounted for 32% and transverse groove type accounted for 26%. (5) Altitude is an important factor that affects the distribution of cold waves, but it is not the only factor; the development of hot and low pressure makes the early temperature rise, which is an important reason for the severe cooling caused by cold air.