Constructing database of population distribution is an essential dynamic part in developing human damage estimation system. According to the regional permanent population and percentage of human activities, population distribution in residential and official buildings could be conveniently estimated by buildings' type and size. However, it becomes to be more complicated for commercial population dynamics estimation. Because "Uncertain Majority" gathering in commercial area are mostly affected by urban characteristics include parameters like commercial scale, accessibility and etc. In this paper, major factors such as commercial building density, shortest time-distance are discussed and a high correlation with region commercial attraction was found. It reveals the possibility to estimate commercial population distribution by urban structure factors.
