Abstract: Hexadecyl trimethyl ammonium bromide(HTAB) was interalated inte the layered montmorillonite,and then blended with polypropylene so as to prepare the polypropylene/montmorillonite nanocomposite. The relationship between ratio of material and the mechanics performance of composite also discussed.The structural characteristics of the composites were studiesd by means of scanning electron microscopy, wide angle x-ray diffraction.The results indicated that the impact strength of composites was increased greatly,the characteristics of the fracture is tough.The type of composites was interalated-stripped.