Abstract: After collecting the data of sensors, communication substation uploaded data to the monitoring host on the ground through CAN bus, so we need a monitor to transform the CAN bus data to the USB data. The design of CAN bus monitor in this paper can collect the data frame and its ID number on the CAN network at the same time. The CAN bus monitor's communication part uses C8051F060 single-chip microcomputer, it can control its built-in CAN protocol controller, USB chip using FT245 as transmission chip. The CAN bus network monitor can work under the condition of various baud rate, can work under the condition of high communication efficiency to achieve real-time data acquisition.