In this paper, the characteristics of lightning activity and its relationship with precipitation are analyzed based on the flash data of National Lightning Detection Network of China from 2010 to 2014 and ground meteorological data from 2010 to 2013. The results show that the lightning activity in Beijing area has obvious diurnal variation. The flash rate varies significantly with seasons, especially negative lightning and all-earth lightning vary the most in autumn. The diurnal maximum and minimum value of flash rate changes with seasons. The diurnal peak hour in spring and summer is the 22:00-23:00 cycle, 01:00 in autumn, and 15:00 in winter, not significantly. The spatial distribution of lightning activity has local variation, with the highest flash density concentrated in the windward slope region of Miyun and Pinggu, the junction area between Tongzhou and the central city. The highest thunderstorm day per year value locates in Yanqing, Changping and western Pinggu, the northern part of Yanqing and Huairou, and the eastern part of Mentougou. The distributions of flash rate and thunderstorm days are incompletely coincident. According to the harmonic analysis of diurnal variation of flash rate, the diurnal cycle is the key variance. The total tendency of flash rate and precipitation in spring, summer and autumn is coincident, while the precipitation changes slower than that of flash rate.