Abstract: Firstly, the paper analyzed the programming logic of track circuit coding from the perspective of the data flow, focused on data communication between train control center and track circuit, implemented the modular simulation modeling of the track section, analyzed the automatic adjusts principle of low-frequency coding to track circuit, realized track circuit low-frequency coding under the four scenarios of section, no route to station, station receiving route, station departure approach by digitizing simulation to Zheng-Xi Line data. The effectiveness of the track circuit coding simulation was validated. It was provided a reliable experimental environment to research on track circuit code for future.