With the acceleration of urban sprawl, many cities have extended their metro lines into peripheral areas. It is hoped that the expansion of transport network can promote the construction of less developed regions and help relieve overpopulation in city centers. When measuring the spatial quality of station catchment areas, land use and transport conditions are two main dimensions that should be paid attention to. But how they affect population distribution hasn't been carefully studied yet. Up to now, there have been a substantial amount of studies relating to the comparatively well-developed transit stations in city centers whereas suburban stations still require further exploration. To fill this gap, our study aims to learn about current land use types, transport conditions and population aggregation around 97 suburban metro stations in Shanghai based on available information and data from Baidu Map and employs a stepwise regression approach to examine how the environmental variables affect population aggregation. The study shows that six land use variables and three transport-related variables are significantly associated with population aggregation on weekday while four land use variables and three transport-related variables show their significance on weekend. By finding out the coefficients of different land use and transport variables, this study hopes to guide government and urban planners in future planning in order to attract more people to live and work around suburban metro stations.