Aimed at requirements of rapid evaluation for colloid stability of lubricating grease in practical application process,a rapid evaluation method was proposed for colloid stability of lubricating grease based on thermal analysis method.This thermal analysis method(TGA and DTA)was applied to study the changing of mass and heat of molybdenum disulfide lubricating grease,and evaluate the colloid stability of two kinds of molybdenum disulfide lubricating greases.The evaluation results were compared with those of oil separation test.It is found that both results are the same.This method can used to evaluate the colloid stability of lubricating greases quickly and exactly compared with traditional oil separation test.