Abstract: In view of the rapid, stable and accurate requirements of train operation system, the linear active disturbance rejection control (LADRC) algorithm was applied to the speed control of ATO system, and the particle swarm optimization algorithm was used to optimize the LADRC algorithm. The parameter tuning efficiency of LADRC controller was improved. Simulation results showed that compared with the traditional PID control algorithm, this algorithm could effectively enhance the rapidity and accuracy of speed control, and improve passenger comfort.