Abstract: The objective of this study is to use advanced electronic computer control and wireless transmission technology to design a precision irrigation control system. It includes computer,soil moisture sensor, irrigation monitor and valve controller. Sensors and valve controllers are connected to irrigation monitor by RS-485 bus. And irrigation monitor is connected to computer by wireless transmission module. This system based on real-time measuring soil moisture content is able to apply water according to soil water content limit for irrigation. The experiment results in field show that the system has the ability to save water in case of getting the soil water content depending on plant survive limits.