In order to identify the meteorological factor and key peroid of Sclerotinia sclerotiorum for oilseed rape over the region along the Yangtze River, and improve the ability of monitoring and evaluating, this paper builds a meteorological grade evaluation model based on precipitation and temperature, using the data including infected plant rate of Sclerotinia sclerotiorum for oilseed rape and daily meteorological data from 1995 to 2019 in Chizhou and Tongcheng, Anhui Province, by the means of linear correlation and regression analysis. Then the fitting test and validation are carried out for the model. The results show that the key period of stem infected is from the late March to the early May. Precipitation is the main meteorological factor affecting the occurrence of Sclerotinia sclerotiorum, and the appropriate temperature could promote the occurrence of Sclerotinia.The comprehensive meteorological index formed by introducing the precipitation coefficient and temperature coefficient, could effectively indicate the comprehensive effect of precipitation and temperature on the Sclerotinia sclerotiorum. The accuracies of the evaluation model for simulation and validation are 86.2% and 85.0% in Chizhou, and 83.8% and 85.0% in Tongcheng, respectively. Therefore, the model established in this study can be used for the monitoring and evaluation of Sclerotinia sclerotiorum in the areas along the Yangtze River in Anhui Province.