Abstract: Huaihe River is located in the climate transition zone between the north and the south of China. It is the most serious drought and flood disaster area among the seven major rivers in China. The analysis of the rain climate characteristics of each sub basin of the Huaihe River Basin will be helpful to carry out its flood control and drought relief work. Based on the daily rain observation data of all rainfall station in the Huaihe River Basin from 1960 to 2018, this paper calculates and selects the area rainfall of Huaihe River Basin and its sub units. Based on the analysis of the annual and monthly rain characteristics and the accumulated value of the 5-day moving rain, it is found that there are significant differences in the rain climate characteristics of each sub-basin of the Huaihe River Basin. The main rainy season of the Huaihe River system is from around June 15 to late July. The main rainy season of the Yihe-Shuhe-Sihe River system is from the end of June to the end of July, but there is a rain concentration period in the upper reaches of the Yihe River and the upper reaches of the Shuhe River in the middle of August.According to the comparative analysis of the data in the front and back 30 years, the annual average areal rainfall has the trend of increasing in different degrees, and there is a good corresponding relationship between the extreme value of 5-day areal rainfall in Huaihe River Basin and the local flood process. The 5-day areal rainfall can be used as a judgment index in practical operation.