To measure the parameters of soilless substrates quickly and accurately, based on a self-made compound sensor for multi-parameter of soilless substrates, combined with ZigBee wireless network technology, a portable wireless detector for multi-parameter of soilless substrates was designed. Considering the practicality and convenient operation, the principle of separated design was employed. The detector included a handheld terminal and a wireless compound sensor. The wireless compound sensor, including a self-made compound sensor and a CC2430 wireless module, collected data of water content, electrical conductivity and temperature in soilless substrates, and sent the data to the handheld terminal by wireless. Then, the handheld terminal received the data through another CC2430 wireless module, and progressed with a MSP430F5438A single chip. The measure results can be displayed, recorded, queried and deleted with the help of a 12864 LCD displayer and a keyboard. The tests demonstrated that error range of water content measurement was -0.4%~3.1%, and relative error range was -3.2%~9.6%; error range of electrical conductivity measurement was -0.015~0.179mS/cm, relative error range was -4.7%~10%; the error range of temperature measurement was -0.63~0.69℃, the relative error range was -1.1%~3.3%. The measurement error of detector was small enough to match the detection precision of agricultural production, and the detector was suitable for different substrates.