This paper aims to explore the flow distribution of pedestrian in underground and ground space of the rail transit station area,and we analyze the affective factors of the trajectory distribution.According to the system spatial relationship,organizational characteristics and commercial facilities and peripheral functions,we know the pedestrian system in the underground and ground space.Then it may enhance the value of the functional area.We take the rail transit station,"Zhongshan Park " Station,as an example.Through the "Gate Count" and "Trace Observation",weve analyzed the organization of commercial function,the space organization and the effect of Peoples behavior in Shanghai "Zhongshan park" rail transit station area.The investigation collected two main aspects of the data,they are the pedestrian flow data and trajectory data.The former research use the "Gate Count" method,in order to get the flow distribution of the underground pedestrian system (Zhongshan Park station area),and then analyze the influencing factors of the flow distribution in the underground pedestrian system and behavior distribution.The latter observation method research using dynamic lines,intended to accurately obtain the flow data which cant fully reflect the specific direction of pedestrians,and further to know the support extent of the flow distribution for each part of the pedestrian system.Then we obtain the influencing factors for the peoples behavior in pedestrian system.Finally,our team summarizes the characteristics ofthe pedestrian flow,the trajectory distribution and the space organization.Furthermore,we focus on the characteristics of flow distribution,the analysis of space organization and the commercial scale,and then we explain the behavior of the pedestrian.According to the summary,the main conclusions are as follows : (1) The Pedestrian flow is very different in the underground pedestrian system,and the flow distribution is not balanced.The import source of pedestrian flow also has an effect on the flow distribution in the rail transit station area (2) There is a very significant correlation between the flow distribution and the spatial integration (R3) in the whole system of "Zhongshan Park" station.If we want to increase the flow distribution of the pedestrian system in the rail transit station areas,we could improve the accessibility of the path (3) In the analysis of scale factors,we obtain the total commercial area and the total number of commercial floors that they have a strong positive correlation with the ratio of the pedestrian flow.It can be said that the scale and commercial facilities have a significant correlation with the attraction of the flow in the "Zhongshan Park" pedestrian system.