For the problem that CAN (controller area network) bus communication bandwidth is limited, a new bus is introduced and a uninhabited aerial vehicle (UAV) flight control computer is designed based on the FlexRay bus. By studying the network structure and internal communication mechanism of the flight control computer, the design of computer hardware platform, internal communication data frame format and synchronization mechanism are completed, and the internal communication software is developed. Actual test proves that FlexRay bus has great advantages over CAN bus in real time, communication speed and efficiency, which satisfies the requirements of real-time information exchange and huge data quantity inside the sample flight control computer.