The soap fiber of lubricating grease is highly entangled as network structural skeletons at the micro level,and the base oil is evenly filled in the gap of structural skeletons.It is needed to sufficiently consider the structural variation of soap fiber during the process of grease properties evaluation and variation mechanism analysis.The characterization methods of lubricating grease soap fiber were explained and analyzed,and an effective characterization method of lubricating grease soap fiber was presented combined with the experimental study of soap fibrous microstructure,that is,the organic solvent extraction and centrifugation method were used to effectively improve the sample preparation effect of soap fiber.The influence factors and laws of grease soap fiber were discussed,it was pointed out that the soap fibrous microstructure was directly influenced by the component of lubricating grease,and the performance degradation caused by the environmental factors was directly reflected by the evolution of the soap fibrous structure.The relationship between the grease performance and soap fiber was summarized,it was pointed out that both rheological behavior and lubricating property of lubricating grease existed the eidetic relationship with the evolution of the soap fibrous structure as well.The future emphases of further studies on soap fiber structure system,that is the quantitative characterization of soap fibrous structure system of lubricating grease,were prospected.