Abstract:This study first defines two new indicators to describe the characteristics of road network structure, one is road network concentration degree, which describes the extent to which the network has a centralized structure, another is structure index of road network layout, which describes comprehensive structure properties from the aspects of road network density and network topology. Then the influencing factors and mechanism which impact on density of public transportation network by road network layout are analyzed. Finally, based on the regression analysis of field data, this study points out that the density of public transportation network is influenced by density of road network and road network concentration degree, there is a significantly positive linear correlation between density of public transportation network and structure index of road network layout.