The invention discloses a cowshed field instrument control system comprising a single-chip microcomputer, a touch screen, a sensor, a wireless module, an upper computer and a control output module. The control output module comprises a solid relay, a fan and a sprayer. The wireless transmit-receive module is connected with the touch screen which is connected with the single-chip microcomputer. One side of the single-chip microcomputer is connected with a temperature and humidity sensor, and the bottom end of the single-chip microcomputer is connected with the control output module. The solid relay controls on/off of the fan and the sprayer. The single-chip microcomputer and the touch screen realize acquisition/processing and displaying of temperature and humidity signals, calculate the corresponding THI value through conversion and transmit the data to the touch screen, transmit the data to the upper computer through the wireless module connected on the touch screen and receive a parameter setting command transmitted by the upper computer. The cowshed field instrument control system is powerful in function and fast in speed and is connected with a high-speed data path through a special communication interface to comprehensively monitor all the units of the system and manage all the information of the whole system so as to be long in the service life.