The soil moisture sensor system is composed of a stainless steel probe and a waterproof probe. It can be buried in the soil and dams for a long time to conduct fixed-point monitoring. And online measurement of the surface and deep soil moisture. Used in conjunction with a data collector, it can be used as a tool for fixed-point water monitoring or mobile measurement to measure soil volumetric water content. It is mainly used for soil moisture detection, agricultural irrigation and forestry protection.