Abstract: The development of the city raised a high demand of traffic, which led to the rapid development of the subway. Subway stations as a water-tight structure, would cause barrier effect to steady groundwater flow. Therefore, it is necessary to study the influence of underground structures on groundwater flow. This paper studies the effect of underground structures on groundwater flow by numerical methods, based on cell-centered finite difference method software Visual MODFLOW.In order to clarify the factors affecting groundwater flow by underground structures, the calculation model was simplified. Model is used only for single layer soil in the underground structure's influence on the groundwater flow. Studies have shown that: underground structures not only can affect the stability time of groundwater flow, but also makes the upstream water level rises, and the downstream water level dropped, whereby, the upstream's degree of influence is bigger than downstream. Water level difference around underground structures between the upstream and downstream, is one of the factors affecting them.