This paper adopted the mixing modification to prepare MAH-POE/ LMW-EP/PP/CaCO3 thermoplastic composites, probed into the structure of composites, the system compared the modification made by composites and the single system of the rheological property, the influence law of flow rate, mechanical properties, dynamic mechanical thermal analysis (DMTA) and the network structure of the composite material etc. The results showed that the elastomer was preferably dispersed in the PP, the two phases have a strong interaction force, When the content reaches 20%, the tensile strength decreased by 7.37%, the elongation at break increased by 410.1%, the impact strength reached 546.3J.m2, there has been broad and strong low internal friction peak tanδ2 peak, and with the increase of elastomer content, liquidity blends decreases, MFR decreases. In short, quadruple composites have optimum overall performance. Polypropylene (PP) is a source of abundant, excellent mechanical properties, good electrical insulation, and resistance to stress cracking and has good overall performance excellent chemical stability thermoplastics. Widely used in medical equipment, auto parts , building materials, home office supplies, as well as a large number of transport and packaging materials [1-3] . However, due to the strong ability of PP crystallization, resulting PP mold shrinkage, impact toughness is poor [4-5] , in order to solve this problem , the current modification methods often used are: copolymerization and blending modification , and blending is the most simple and effective toughening PP method . The main focus ① blended with a modified rubber or thermoplastic elastomer blends toughening ; ② Toughening with other organic polymers ; ③ rigid inorganic particle toughening ; ④ elastomer / toughening common inorganic particles [6-10] . POE because both thermoplastic plastics , but also the crosslinkable rubber , which has a small cohesive energy , high shear sensitivity , and good compatibility with PP machining , toughening modification of PP the effect is significant and widespread attention , but the larger POE elastomer modified PP viscosity , processing performance be affected [11-13] . In this paper, LMW-EP and MAH-POE-modified PP, while adding CaCO3 prepared by a four-element composite elastomer material, by contrast, explores the compatibility of the quaternary blends, processing fluidity and mechanical properties