Abstract: The mechanical properties the crystallization of matrix of glass fiber-reinforeed PP aml their dependence on the interfacial, dhesion have been studied by using seamning electron microscope,infrarel spectrometer,material universal testing machine,polarizing microscope and DSC. etc.The results show that in the compounding process of glass fiber and PP,the added interfacal, reactive agents and the formed product from their grafting with PP cai react with the multilayer silicane coupling agent on the surface of glass fiber, and obviously increase the interfacial phase module,the interfacial bond strength and mechanical properties of the compocite.PP,Meanwhile,it was found that the produced interfacial stress from the contraction of the matix in injection molding can strain-induce the crystallization of matrix and leads to obvious change about the morphology and the crystallinity of matrix,and that the interfacial band strength is an im portant factor of producing the straininduced crystallization and controlling the strain-induced crystallization as well as controlling the multiphase crystallization.