The temperature and moisture of single soil layer is difficult to represent the real growth environment around crop root. The measurement of temperature and moisture in multilayer and multipoint soil is easy to know water demand around crop root during its growth period deeply and accurately. It also can improve the water utilization coefficient and achieve basic data for the research on soil water infiltration variation and intelligent precise irrigation. In this paper, a monitoring system for multilayer soil temperature and moisture was designed based on WSN using the core ship CC2530. The system consists of three parts: monitoring nodes, a gateway node and a system platform in upper computer. The monitoring system was deployed in farmland. A lot of soil temperature and moisture data was got in real-time, and the changes of soil temperature and moisture in four soil layers with depths of 10cm, 20cm, 30cm and 40cm were obtained. The application in the farmland shows that the system is practical, functional and stable.