After nearly a decade of development, the operating mileage of the Nanjing metropolitan rail transit network has reached 200 km, with significant advantages of wide coverage, high connectivity, and strong extensibility. The network strongly supports the expansion of the urban space, drives the land development along the transit line, and improves the accessibility of suburban residents. It also plays an important role in the urban agglomeration process of the Nanjing metropolitan area. Furthermore, with the movement towards the regional development integration of the Yangtze River Delta, there is a need to build a high-level comprehensive transportation system to fulfil the growing demand for high-quality travel experiences, therefore the metropolitan rail transit system will need to be improved in respect to speed, flexibility, and interconnectivity. Specific measures to achieve this goal include optimizing the operating organization mode, upgrading the network layout and cohesion, judiciously making choices on speed and the power supply system, and coordinating the timing of land development along the route.