Abstract: Taking the centrifugal compressor unit in Yinchuan Compressor Station of LanYin Gas Transmission Pipeline as an example, cleaning principle and technical method for lubricant oil system of compressor is introduced. Cleaning requirements and testing method of lubricant oil cleaning are proposed and cleaning steps are summarized. Practice shows that the cleaning method not only ensures quality of lubricant oil. but also shortens cleaning time of the lubricant oil system, which is a practical method to ensure safe running of the compressor units.