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There exists a severe but normal problem that the crop fertilization is uneven such as over or too less fertilized and the concentration can't be well controlled.As to this situation, this paper presents the precision fertilization system, which can improve saving irrigation water and water resourceefficiency.A precisionfertigationsystem is designed by using self-designedfertigation machineand data acquisitioncontroller, as well as data transmission with distributed network and remote network.The system realizessoil moisture monitoring, injecting fertilizer control, mixed fertilizer control and expert decision support.With the help of advanced automatic fertilization program, irrigation and fertilization programs, traceability management system and cloud service module, the system can control the quantity and time of irrigation and fertilizationaccurately.The system is divided into three parts: lower embedded controller, upper industrial personal computer (IPC) and the remote terminal.Lower embedded controller: It mainly receive the set value and output command of IPC, acquire sensor signal and process, and drive output signal.Upper IPC: It is mainly responsible for the information exchange of human-machine, the show and comparative of set value of various parameters, the calculated values and measured values.It also use various control strategies and algorithms to adjust the closed control loop.Meanwhile it sends control output command to the embedded controller and draw major parameters in real time curve,historical curve.It is also responsible for the database management.It is able to query and analyze the relevant data.Remote terminal: It provides the remote monitoring platform for the management staff.The staff can access the intelligent fertigation management system to view information on the cultivation of irrigation district, irrigation status, control of irrigation and fertilization after entering the user name and password and accessing WIFI, 3G, 4G and other network, through mobile phones, tablet computers and other equipment.Upper and lower embedded controller is connected by CAN bus, upper IPC communicate with the remote terminal through the Ethernet, WIFI, 3G or other ways.The system follows irrigation and fertilization control algorithm of irrigation district.When receiving irrigation requests from several cells simultaneously, the sum flow should be no more than the maximum flow of the fertilization system.When receiving fertilization requests from several cells simultaneously, only one fertilizer formula can be used for irrigation, others stay in order set up by the system.They can only go on after the former one is finished and the pipe is cleaned and also follow the same irrigation order as the last one.Meanwhile, when fertilizing with nutrient, the computer will mix up water and nutrient according to the EC, pH value set before of the formula by mixed fertilizer.Meanwhile, EC, pH value of mixed nutrition is online monitored,the switch frequency will be adjusted reference to deviation between the set value and actual value of EC, pH so as to make the deviation in the tolerance in a short time.The system can realize real-time soil moisturemonitoring,injecting and mixed fertilizer control based on ratio of fertilizer or set value of EC, pH, automatic irrigation control based on parameters of water demand bydifferent crops in different growth phases and crop management.Application in demonstration areas proved that, the system is stable, reliableand easy to operate, which will greatly enhance the coupling effect of water and fertilizer and fertilizer efficiency and improve the yield and quality.It can be widely applied in such fields as large-scale planting, greenhouses and orchard.It is of great significance for the implementation of precisionagriculture.