It becomes significant and inevitable that a need arises to review or examine over environmental concern on assemblage of throwaway, exceptionally plastic outcomes and in follow up it becomes important to pivot on exploring engineering materials, which are of biodegradable nature. However, this is not appraised as a biodegradable material on a complete extent, it would be recommendable to initiate by selecting natural, decomposable reinforcement materials, assimilated into recyclable polymer matrices to fabricate composites that are inert to surroundings and habitat. The composite evolved comprises vetiver grass, prepared into fibre and particulate forms, to reinforce a polymer matrix of High-Density Polyethylene (HDPE), consequently decrease the constitution of the polymer, while concurrently upgrade its mechanical properties. Different reinforcement compositions and time period of chemical treatment of the reinforcing material were also done to give a better picture of the augmentation of properties of the material. Several mechanical properties were examined namely tensile, flexural, impact and hardness tests, in accordance to ASTM and ISO standards.