Along with the urban space systematic,three-dimensional trends,a large number of urban rail transit sites are under construction,forming underground comprehensive public space which in close coordination with the ground and traffic as dominant function.Walking pattern in underground pedestrian system can be considered as a series of gathering,separating and crossing in tunnel.Eventually there will be more people flow and related activities on some channels,while others are just the opposite.If we want an effective and economical planning and design,then we need to know the explanation to the distribution of flow and activities,which makes it important to study the flow distribution in underground pedestrian system and its influencing factors.In this paper,we choose Jingan Temple Subway station underground pedestrian system as a case study.Based on information gathered from on-site investigations,weve analyzed the impact of the spatial layout of the underground pedestrian system on flow distribution.The study found: the depth of underground space which is relative to import point,integration and actual distance,width of underground pedestrian passage all have impact on the flow distribution.We can see that the intensity and location of generator of pedestrian flow have important effects on pedestrian distribution in underground pedestrian system.However,according to our scatter diagram of pedestrian flow and commercial interface ratio,the two barely have obvious linear relationship between each other.Usually,the commercial economic factors as format are important reference points to attract pedestrian flow.In Jingan temple case,the ratio is small for peoples main purpose is transportation rather than shopping.So we assumed that there were no obvious and relative relationship between commercial interface ratio and population flow.Through a MR model,we confirmed when considering spatial factors such as the depth of underground space relative to import point and underground pedestrian passage,we can better explain the flow distribution in Jingan Temple Subway station underground pedestrian system.The model can explain 51.9% of distribution inunderground pedestrian passage,and the other may be affected by unmentioned factors,such as time quantum,layout,individual familiarity to environment and purpose of behavior,and all these may affect the distribution importantly to some extent.The factors concerning distribution of population flow are numbers and complicated,with inter mechanism of action.