In order to decrease the cost and improve the testing efficiency, a four channel detection system for soil macronutrients rapid determination was developed and evaluated. The system was mainly composed of an ion selective electrodes (ISEs) array, a laptop computer, a microchip and the signal conditioning circuit. As a sensing unit, the ISEs array was integrated with a pH electrode, a nitrate ISE, potassium ISE and a phosphate ISE. According to the testing results, the input impedance of each channel was around 1012Ω, and the input current was about 1pA. The detection range was between -2000~2000mV,which indicated the good compatibility with the majority of ion-selective electrodes. According to the validation results, the testing accuracy and detection range of soil pH value, nitrate-nitrogen and potassium could meet the needs of site-specific fertilization.