Abstract: Lightning observation may play a key role in the monitoring of deep convection over the Qinghai-Tibet Plateau, especially considering that the wide-range and real-time observation ability of lightning location system. It is firstly necessary to understand the relationship between lightning activity and deep convection features, which, has been rarely concerned in the Qinghai-Tibet Plateau. Using radar data and cloud-to-ground (CG) lightning data during May-September from 2014 to 2015, correlations between CG lightning and radar parameters of thunderstorms are investigated over Naqu, a county in the middle of the Plateau with relatively strong lightning activity. Continuous spatial regions of radar composite reflectivity above 20 dBZ are identified as storm cells at each 6 min radar volume scan, and "matching ellipses" are used to enclose the scope of cells, and then whether CG lightning flashes fall in ellipses or cells is decided. Cells with lightning and located within 30-100 km of radar center are picked out as thunderstorms. Based on 5626 thunderstorm samples, it is summarized that the maximum radar echo, 20 dBZ echo top and 30 dBZ within 5 km of CG flash location exhibit normal distribution, with their peak values ranging from 34 to 41 dBZ, 11 to 15 km, and 8.5 to 12 km, respectively. Meanwhile, the maximum vertical integrated liquid content and the maximum precipitation ice content vertically integrated at 7-11 km both show logarithmic normal distribution. A total of 4719 thunderstorms that possess no less than 30 dBZ reflectivity (a threshold value for the definition of strong reflectivity) are selected for the correlation analysis. Weak correlations between CG lightning frequency and radar parameters are found while are considered as one-to-one relationships. However, correlations enhance prominently when the CG lightning frequency in the thunderstorm increases. The correlation study based on interval segmentations of radar parameters is then made and strong relationships are found, indicating the macroscopic correspondences of CG lightning frequency to the intensity of thunderstorms. The area of composite reflectivity no less than 30 dBZ show the most outstanding correlation with CG lightning frequency among radar parameters which are segmented linearly, with the correlation coefficient being 0.75. Among radar parameters that are segmented according to their logarithms, the logarithm of precipitation ice content accumulated at 7-11 km and in the area with composite reflectivity no less than 30 dBZ are most prominently correlated with CG lightning frequency, with the correlation coefficient being 0.95. Formulas based on linear fittings and power function fittings are all given, while the power function fittings are a little better according to their corresponding correlation coefficient.