 An experimental investigation was conducted to determine the optimum fiber content and the effect of alkaline treatment on Kenaf fiber-reinforced epoxy composites. The research involved two phases. In the first phase, specimens with different fiber weight fractions were fabricated and tested for tensile, flexural, and impact properties, and in the second phase, the optimal fiber weight fraction was chosen to investigate the effect of chemical treatment on mechanical properties. The results showed that the optimum fiber content was 40% with a tensile strength of 45.98 mPa, flexural strength of 40.50 mPa, and impact strength of 13.26 kJ m2. Additionally, 6% NaOH treatment resulted in the highest mechanical properties, including a tensile strength of 58.34 mPa, flexural strength of 55.34 mPa, and impact strength of 16.69 kJ m2, as well as improvements of 26.88% 37.28% and 25.87% in tensile, flexural, and impact strengths, respectively.