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In the summers of 2009 and 2010, observation experiments of lightning flashes striking on tall buildings to the southeast of Guangdong Provincial Meteorological Service were conducted. The video recording data obtained by ordinary cameras were processed and analyzed. Based on the characteristic analysis of pixels number distribution with different brightness variation values, a video data processing program was devised to extract lightning pictures from video recording data. The characteristics of natural lightning on tall buildings in the viewing range were statistically analyzed. The results show that the mean duration of 87 natural cloud to ground lightning striking on tall buildings in Guangzhou is 348 ms. By comparing the lightning flashes striking on buildings higher than 500 m with those with heights from 100 m to 500 m, the average number for the former is significantly larger than that of the latter, and the mean duration of the former is longer. Some video images of “spider” flash and long discharge are also presented.