Abstract: In making an improvement on the interfacial adhesion between aramid fiber and matrix,the Motewo.Takayanagi Chemical Method was used to treat the skin layer of aramid fiber with polyfunctional opoxide.The surface structures of treated fiber were studied by IR,ele,ental analysis and XPS.The average graft degree of epoxidc on the surface of fiber was obtained for about 88mol%,which was gained from calibration curves.In this paper,the strength of interfacial adhsion was measured by Pullout Tost of monofilament.The used fiber was Aramid 1414 and the matrix was cpoxidc.Experimental rosulte showed that the interfacial adhesion strongth increasis.On the other hand,the effect of matrix on the interfacial adhesion strengh is important.The fracture surface morphologies of pulled out fiber and matrix cavity were observed bu SEM and some analysis of the damage mechanism was described.