Abstract: Starting from the analysis of FAO (fully automatic operation) scenario, the functions of FAO platform screen door and conventional one are compared. Research is carried out on system architecture design considering the configuration safety requirements, functions and interfaces of platform screen door in FAO urban rail transit. As a key point, the interface, type and purpose of platform screen door, signaling system and integrated monitoring system are standardized.At the same time, based on the operation status of Taiyuan rail transit Line 2, relevant optimization suggestions are put forward for the linkage time of platform screen door and train door, the number of gap detection devices and the integrated design of PSL (platform scree local control) box and gap detection device operation panel in FAO system.