Abstract: In this paper, an interlock water-saving irrigation control system was designed by using sclf-designed irrigation control devices and soil moisture monitoring devices, as well as data transmission with GSM network. The system has the functions of soil moisture monitoring, alltomatic irrigation control and expert decision support, and advantage of saving irrigation water, more efficient utilization of water resource. It consists of three parts, the onsite control cabinet, data collection system and automatic control software. The system can realize real-time soil moisture monitoring, expert knowledge management, and automatic irrigation control based on parameters of water demand by different crops in different growth phases. Application in demonstration areas proved that, the system is stable, reliable and easy to operate. It can be widely applied in such fields as large-scale planting, greenhouses and precision agriculture. It is of great significance for the implementation of water-saving agriculture.