In order to solve the problem of interference and inconvenience due to the use of wired signal transmission between the driving cab and the power supply car of the electrical excavator, the wireless signal transmission solution is proposed. With STM32 microcontroller as the core, use Modbus protocol to collect data of power supply car, and obtain the electric state and data of the electric excavator. ZigBee communication protocol is applied to transmit the data to the STM32 micro control panel in the cab for display, at the same time to receive the speed and other instructions of the cab to command the inverter of power car. Experimental results show that the working states acquisition and the wireless bidirectional data transmission is stable and reliable, and the various functions are realized successfully. It can be prospected that such a wireless bidirectional data transmission solution will be used in a wide range of applications.