A distributed flexible strip-type soil moisture sensing and detection system based on the principle of parallel transmission line distribution parameter measurement is introduced. The changes of soil moisture in some regions will cause the changes of distribution impedance in the strip-type flexible strip-type parallel transmission line which buried in the soil, when a high-speed pulse signal transmit through the transmission line, and the changes of distribution impedance lead to a reflected signal of the pulse in time domain. The soil moisture around the transmission line can be measured by studying the reflected signal. The results of experiments shows, the distributed soil moisture measurement system is able to measure the soil moisture changes of any regions around the long-distance transmission lines. Through this transmission line sensor, it can realize the monitoring work of the soil moisture changes and gradient of changes on different layers or different regions, and the system is quite suitable for the early warning of geological disasters and agricultural scientific production applications.