Abstract: Based on Microsoft Train Simulation (MSTS), the open-source game software Open Rails (OR) was developed. This article combined with the structure of the Automatic Train Control (ATC) system, designed the MSTS based Automatic Train Operation (ATO) system functional modules simulation, used socket network communicational technology in .Net platform to establish the function module simulation of ATO system, implemented the function of remote control OR train client. The integrated control mode provided the communication interface and the automatic operation control basis for the extensional function of the ATO system, improved the overall authenticity of the train simulation system. It had important significance to improve the whole system simulation platform, achieved the objectives and expected results.