The paper introduced a design scheme of host-standby mode hot-standby of pump control system of coal mine, described working process of hot-standby and introduced overall design and designs of basic business flow and take-over control flow in details. Two controllers exchange data through heartbeat frame. The pump control system solves problems of simultaneous power-on and fighting for controlling power during initialization of the two controllers by comparing switching time and value of address of the controller, and avoids failure of the host controller during the course of equipment start or stop which may cause equipment loss of control by the standby controller taking over controlling power. The scheme implements automatic switching over between host controller and standby controller, achieves purpose of continuously running of the system, and improves stability of the system.