Topographic environment is one of the important factors affecting lightning activities. Fully understanding the characteristics of lightning activities under different topographic condition is the premise to construct transmission lines effectively and improve the lightning protection schemes. Based on the topographic parameters in Yunnan province and the monitoring data of lightning activities accumulated for recent years, the correlation between the topographic factors, such as altitude, slope, aspect, topographic location, surface coverage type, and lightning characteristic parameters, such as lightning density and lightning intensity, is analyzed with the data mining technology. The results show that the type of the topographic factors have a greater impact on the cloud-to-ground flash density than the flash intensity. While the land cover type has a noticeable impact on both flash density and intensity.