In this paper, 0.05 grade three-phase main control system of multi-station meter testing equipment (MTE) is presented. This design is based on the S3C2440 core board as the control core, and the software is based on Windows CE(WINCE) embedded operating system. The device is displayed and controlled by 7-inch Touch Screen. The main control system communicate with the error instrument and PC through Controller Area Network (CAN) bus, and the largest number of error instruments can connect to CAN bus is 100. The main control system communicates through RS232 bus with three-phase signal source and standard electric energy meter, through RS485 bus with programmable power amplifier. In this device, calibration of energy meters can not only through the PC software, but also use the main control system. Compared to the traditional design of the electric energy meter calibration device, the design’s the man-machine interface is more optimized, the number of electric energy meters can be test in the same time is more, faster communication, stronger anti-interference ability, and calibration is more efficiency.