Abstract: Using the observational thunderstorm data of 30 stations in southwestern Henan province during 55 years, the spatiotemporal variation of thunderstorm days in southwestern Henan province are analyzed by means of mathematical statistics, the wavelet analysis and the empirical orthogonal function method. The results indicated that: The inter-annual variation range is bigger and stage change is more obvious, the numbers of thunderstorm days are decreasing and mostly occur in summer. From 1960s to the early 21st century, there are 8 years short period and 17~19 years long period. The anomaly variation of thunderstorms in whole area are consistent, under the influence of climate characteristics, the thunderstorm days change has the northsouth differences taking the Qinling MountainsHuaihe line as a boundary,and meanwhile exist the local features.