Abstract: In order to make the crops grow under the condition of appropriate water content and realize the precision irrigation of farmland, an intelligent irrigation system based on LoRa communication technology was designed in this paper. The system mainly includes crop information acquisition unit, LoRa wireless communication unit, intelligent decision unit and irrigation output module. The system adopts MSP430 processor and WH-101-L LoRa module to realize low power consumption and network terminal node design, transmits farmland crop information to cloud server through concentrator gateway, and builds cloud management decision software. The results of system application test show that the wireless crop awareness network using synchronous wake up technology has stable data transmission, the average packet loss rate is 0.3%, and has strong scalability. The system calculates irrigation amount and irrigation time by intelligent decision unit based on real-time crop information and database, and remotely controls the irrigation output module to accurately control the soil moisture content of crops in different growing periods. The mean square errors of water content obtained in blueberry and corn test fields are 1.80 and 4.83 respectively, both lower than the traditional irrigation method.