Abstract: With the progress on the research of lightning hitting high buildings, influences of high buildings on characteristics of cloud-to-ground lightning flashes in the nearby area still need further research. At present, this kind of research are mainly based on data obtained by lightning location system, while optical observations are more visible and should be better considered. Results of optical observations can deepen our understanding of high-building impacts on characteristics of downward cloud-to-ground lightning flashes activity in nearby areas and provide basic data for lightning protection design of high buildings and nearby areas.Based on optical data of Tall-Object Lightning Observatory in Guangzhou (TOLOG) from 2009 to 2014, combined with the lightning acoustics and electromagnetic field variation waveform data, distribution characteristics of 119 downward cloud-to-ground lightning flashes in the northwest of Canton Tower within 3 km in 60° sector region are analyzed statistically. Results show that 43.7% (52/119) of downward cloud-to-ground lightning flashes occurs on four tallest buildings in the area. Lightnings hit Canton Tower, Canton West Tower, Canton East Tower and Guangsheng Building for 20, 12, 10 and 10 times, respectively. Besides 20 (16.8%) flashes directly hit Canton Tower, no downward lightning is observed within 1 km distance from Canton Tower (11.1% of total area). The closest stroke point to Canton Tower is about 1.2 km away. 35 (29.4%) lightning flashes are observed in the area of 1-2 km away from Canton Tower (33.3% of total area). Building lower than 300 m is hit no more than once in the area each. 64 (53.8%) lightning flashes are observed in 2-3 km away from Canton Tower (55.6% of total area). Some buildings with a height below 300 m are hit more than once, up to 5 times. The attraction of Canton Tower to downward cloud-to-ground lightning flashes makes no downward cloud-to-ground flashes observed in the vicinity of 1 km or so. The relative density of the flash (excluding flashes hitting buildings with a height of more than 300 m) increases gradually with the increase of distance. Results indicate that the attraction of high buildings to the downward cloud-to-ground lightning flashes gradually weakens with the increase of distance.