Based on the meteorological data from 1961 to 2003 in Jiangsu Province,the statistical analysis indicates: 96% to 98% thunder days occurs in March and September,and the number of thunder days is 27 to 36 days in a normal year.The area around the Taihu Lake sees thunder days most frequently,whereas Xuzhou the least,and the Lixiahe and Hongzehu Lake region is in the middle.The number of thunder days can change greatly year by year with the maximum value being 2.5 times as great as the minimum one.For the characteristics of atmospheric circulation factors on 500 hPa can indicate weather trend and control weather condition,a number of factors are selected as prediction factors,which are highly correlative,stable and independent,and the prediction model of atmospheric circulation patterns for thunder days in Jiangsu Province is developed.These patterns can be used in practical forecasting and get good results.