Public transit network has a wide range of data, its storage, display, and management process is very complicated. The use of TransCAD software contribute to establish intuitionistic public transit basic data system which would has strong maneuverability and clear layer-structure. In this paper, the construction method, pertinent attribute settings of basic data system based on TransCAD software was discussed, which is applied to Urumqi case , it realizes the visualization of public transit network editing and attribute data processing by integrating vector graph and database, then achieves the functions of inputting, modifying, counting and inquiring the network data. The network information can be dynamically updated on the basic data system which offers accurate and complete test data for the planning and design of public transit system.