The invention discloses a high-pressure degreasing cleaning method for the inner wall of an oxygen pipeline. The method comprises the technological processes of carrying out water washing and pressure testing on a pipeline system, carrying out primary degreasing, carrying out water washing, carrying out acid pickling, carrying out water washing, carrying out secondary degreasing, carrying out water washing, carrying out passivation, carrying out manual inspection, and carrying out dry oil-free air or nitrogen purging drying, wherein in the cleaning process, firstly, the pipeline is fully filled with cleaning fluid and is connected to a cleaning pump station through a temporary pipeline to form a forced circulation cleaning loop, and then the cleaning fluid is driven by a power system to circularly and continuously wash the interior of the pipeline. According to the method, oil stains, welding slags and other mechanical impurities generated in the manufacturing, transporting, storing and installing processes of the pipeline can be removed so that the inner wall of the cleaned pipeline can meet the required cleanliness.