In this research, vetiver grass was used as a filler in polypropylene (PP) composite. Chemical treatment was done to modify fiber surface. Natural rubber (NR) and EPDM rubber at various contents were used as an impact modifier of the composites. The composites were prepared by using an injection molding. By adding NR or EPDM to PP composites, a significant increase in the impact strength and elongation at break was observed in PP composite with rubber content more than 20% by weight. However, the tensile strength and Young’s modulus of the composites decrease with increasing rubber contents. Nevertheless, the tensile strength and Young’s modulus of the composites with NR or EPDM are still higher than those of PP up to 10% and 20% rubber contents, respectively. Comparisons between NR and EPDM rubber on the mechanical properties of the composites were elucidated.