This paper surveyed the people stampede accidents have occurred in the crowded public place all over the world in recent years. Combine with investigating the theory of gathering risk，the psychology of gathering crowd，behavior and movement characteristics，etc，the PMCDT model and crowd stampede risk model were used to study and analyze the serious accident happened at shanghai bund，as a result，the reason of the stampede was obtained and the prevention measures to the risk of crowded public place were presented.