Abstract: In view of the problems that the lack of portable CAN bus analysis equipment to quickly locate the CAN bus network fault nodes, interference elimination and reliability testing in the process of installation, debugging and daily maintenance of various CAN bus equipment in the coal mine, a portable mining CAN bus analyzer based on CAN bus analysis theory was researched and designed. The analyzer uses the main control chip STM32F429 as the core, and realizes the functions of CAN bus baud rate self-recognition, bus quality analysis and fault detection, message parsing, display and storage. The test results show that the analyzer can accurately analyze the communication quality of the bus and identify the bus faults which have important practical significance for the rapid troubleshooting of the bus faults and the improvement of the rationality and reliability of the bus network.