This paper takes the underground connection space formed by all subway stations and underground commercial space of commercial complexes in the Fourth Ring Road area of Beijing as the research object,classifies the space based on the relative positional relationship between subway stations and commercial complexes,and sorts out 21 subway stations and 36 connections spaces that meet the research requirements.According to the three different location relationships,the existing underground connection spaces in Beijing are divided into five connection modes,which are mainly classified as open connection mode,hall connection mode,channel connection mode,square connection mode and surface cover mode.Finally,the influencing factors of the connection patterns between Beijing subway stations and commercial complexes are discussed based on the investigation results.