In the hall of University of Tsukuba, it is often crowded of many people because of some problems, which are come from characteristic of the space. Crowded situation has various risk, some are close to us and others might lead fatal problem. The purpose of this paper is to analyze the relation between flow of crowd and characteristic of space based on a computer simulation developed. It is come out that most possibility space of crowding in the hall is just inside of the entrance.