Abstract: Polypropylene (PP) was grafted with glycidyl methacrylate (GMA) to prepare functional PP (PP-g-GMA) by melt grafting reaction. Then PP-g-GMA was coupled by a coupling agent, polyhexa methylene guanidine (PHMG), which contained two primary amine groups at two ends of the molecule, to prepare a coupled PP (MPP). Compared with the general PP (EPS) and the commercially imported PP (PF-814), the melt rheological properties of the prepared MPP were investigated. Results showed that the storage modulus at low frequency region, the extrusion swell, the steady state compliance, the zero shear viscosity and the melt strength of MPP increased in comparison with EPS and PF-814.