Debris flow is a common geo-hazard, with characteristic of suddeness, short duration, ferocious power and strong destruction and so on. From top-down, the gully debris flow can be divided into formation zone, circulation zone and accumulation zone. Based on the characteristics in occurring stage, movement stage and damage stage, a debris flow automatic monitoring system was composed of several subsystems and an integrated control center. The subsystems included rainfall telemetry, ground acoustic telemetry, mud-position telemetry, wired mud-location, impact force and camera monitoring. Each monitoring station of the system was equipped with power and automatic control. The aparatus has a high integrated level, which is easy to carry out field monitoring under various conditions. The system can monitor the debris flow quickly and accurately so as to reduce the damage of debris flow.