Poor compatibility affects the performance of polypropylene/talc composites. In order to improve the adhesion at the interface between the polymeric matrix and the fillers, in most of the cases the non-polar filler should be modified with a compatibilizer or coupling agents. An overview of our current research on the effect of the addition of silane treated- and untreated- talc powder on the mechanical properties of polypropylene/talc composites is presented in this paper. Different silane coupling agents (3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane and 3-methacryloxypropyltrimethoxysilane) were used to improve the adhesion at the surface of talc powders. Maleic anhydride grafted polypropylene (MA-g-PP) was utilized to increase the adhesion between the polypropylene matrix and modified talc powders. The content of MA-g-PP was varied between 1 and 5 wt% in polypropylene/talc composites. The surface modification of talc powders has a significant effect on the interfacial structure and the mechanical properties such as tensile strength and impact strength of polypropylene/talc composites. The experiments show that polypropylene grafted with maleic anhydride acid exhibits the highest potential for improvements in this field.