In order to explore the preparation process of graphene?reinforced composite materials with industrial development prospects, graphene/polypropylene composite materials were prepared using the melt blending method, and the graphene reinforcement mechanism was analyzed through experimental and computational analysis. The results indicate that through melt blending, graphene can be uniformly dispersed in the matrix. The tensile strength of the composite material with a graphene mass fraction of 0.5% is 50.3 MPa. When the mass fraction of graphene is 4.0%, the elastic modulus and tensile strength of the composites are increase by 77.1% and 22.5%, respectively, compared to the polypropylene matrix alone. The uniform dispersion of graphene and the interaction between graphene and the polypropylene matrix enable effective stress transfer at the graphene/polypropylene interface.