Abstract: Aiming at the disadvantages of the methods of the present on-line measuring soil moisture content, the soil moisture content real-time measurement system was designed based on a new type of TDT soil moisture content sensor. The system measurement results showed that the sensor sensitive part was located in the upper portion, and the sensor embedded suggestion was given. The system had simple structure, convenient operation, not affected by salinity effect, easy to realize the characteristics of soil moisture content network measurement.