The long-term friction between bearing outer ring and bearing table in CNG compressor causes excessive tolerance and results in great vibration and noise,which has seriously affected the normal operation of the equipment. For above problems,the oxygen-acetylene flame spraying repair technique of bearing outer ring is researched. The results show that this method can minimize the deformation of the workpiece,and the coating is closely combined to meet the requirements of use. It can effectively solve the problems of vibration and noise caused by excessive tolerance between parts,thus effectively prolonging the service life of the bearing outer ring in CNG compressor. The method is simple,economical and worthy of being popularized in production.