Abstract: In a certain gas booster station, the vibration of centrifugal compressor exceeds the criterion due to the scaling of its rotor, and consequently the centrifugal compressor is shutdown. In this paper, the failure mechanisms of the centrifugal compressor were analyzed by means of the state monitoring technology, combined with transport capacity change of compressor, endoscope detection, and disassembly maintenance. It is confirmed that the cause of the rotor imbalance is the impeller scaling. Then, tests and cause analysis were carried out on the scaling buildup of impeller and passageway, and the practicality and effectiveness of the fault diagnosis technique were verified. Finally, the prevention and control measures were put forward, e.g. strengthening filtration and drainage. The research results provide the reference for the diagnosis and treatment of similar faults of centrifugal compressors for long-distance natural gas pipelines.