Abstract: The synergy of corrosion and wear in the fretting corrosion of ICrl3 stainless steel in NaCl solution was studied by means of the fretting corrosion measuring and testing system. In the experiments, it would be found that cathodic protection can not completely inhibit corrosion of ICrl3 in 3.5%NaCl solution. Liquid lubrication effect on weight loss is contrary to synergetic effect, so lubrication effect should be differentiated from synergetic effect. A new mathematical model was presented to qualitatively estimate synergetic effect of corrosion and wear.