The utility model provides a communication system applied to engineering machinery vehicles. The system comprises an upper device and a chassis device, wherein the upper device is used for work of the engineering machinery vehicles and the chassis device is used for running of the engineering machinery vehicles. The upper device comprises a first wireless communication module used for the chassis device to transmit data. The chassis device comprises a second wireless communication module used for transmitting the data with the upper device. The first wireless communication module and the second wireless communication module are in wireless connection. The upper device and the chassis device are respectively provided with a wireless communication module and a wireless transmission method is adopted to carry out internal data transmission, so the communication system solves the problems that cost of wire communication between the upper device and the chassis device is high, and installation, debugging and maintenance are difficult, lowers equipment cost, and enhances property of the engineering machinery vehicles.