Abstract. The increasing demand for eco-friendly and recyclable materials has driven the development of natural fiber-based composite materials. This study aims to analyze the effect of volume fraction variation on the mechanical properties of hybrid composites made from coconut coir fiber and banana stem fiber with an epoxy matrix. The research employed an experimental method with variations of fiber volume fractions at 40%, 30%, and 20%, and mechanical testing including tensile, bending, and impact tests based on ASTM standards. The results showed that the highest tensile strength was achieved by the composite with a 60% matrix and 40% fiber volume fraction, reaching 21.16 MPa. Meanwhile, the highest bending strength and impact resistance were obtained by the composite with an 80% matrix and 20% fiber volume fraction, at 49.46 MPa and 0.00837 Joule/mm², respectively. Increasing the fiber content tends to enhance tensile strength but reduces bending strength and impact resistance due to uneven resin distribution and the formation of voids. This hybrid composite has potential as an environmentally friendly material alternative with competitive mechanical properties.
