The thunderstorm strength from June to August in 2011, 2012 and 2014 is classified by using the data of lightning location in Qingyuan, Guangdong Province, combined with the radiosonde data, calculating some parameters that can reflect the stability or energy relationships of the atmosphere, such as the Convective Available Potential Energy, Showalter index and K index and so on. Then we analyze the distribution of these parameters before the occurrence of the different intensity thunderstorms in different time. The results show that the Showalter index, Lifted index, K index, Total Totals index, SWEAT index and Convective Available Potential Energy have a certain correlation with the intensity of thunderstorms, while Convective Inhibition, Bulk Richardson Number and the intensity of thunderstorms are not found to be well correlated. Among them, the Showalter index before the occurrence of thunderstorms in Guangdong is less than 0 ℃, the Lifted index less than -2 ℃, the K index greater than 30 ℃, and the Convective Available Potential Energy greater than 500 J/kg, which is more likely to produce moderate to strong thunderstorms. At the same time, the K index in Guangdong is about 20 ℃ higher than that in the Tibetan Plateau, and the average value of Convective Available Potential Energy is about 300 J/kg higher than those in the Tibetan Plateau and Shaanxi, Gansu, Ningxia. The distribution characteristics of other parameters are similar to those in some regions, which further reflect the particular characteristics of thunderstorms in Guangdong and help to understand the characteristics of thunderstorms in Guangdong.