Abstract: Surge is a type of vibration of centrifugal compressor under abnormal operation condition when the flowrate is reduced to certain level. The paper introduces the physical process of surge of centrifugal compressor, deeply analyzes various surge causes, and concludes the primary cause. It analyzes the hazards of surge to the running of compressor, such as seal and O-ring, movable vane, bearing and ring sealing oil system, the adjusted clearance value between compressor parts and the integrity of shaft. Combined with the actual running condition, it provides the prevention measures against surge from the aspects of running of compressor, including widening the stable operating condition area, increasing the process gas flow to compressor intake, controlling the start-up and stop process, reducing the pressure ratio of compressor, decreasing the rotational speed of compressor set and avoiding the compressor set from approaching the safety alarm limitation frequently, etc..