The aim of this study is to investigate the effect of alkali and SLS (Sodium Lauryl Sulphate) treatment on Banana/Kenaf Hybrid composites and woven hybrid composites. The fibers are treated with 10% of sodium hydroxide (NaOH) and 10% Sodium Lauryl Sulfate (SLS) for 30 minutes. Woven banana and kenaf fiber reinforced unsaturated polyester (USP) composites were fabricated by moulding technique. The fiber content in the composite is kept constant to 40 %. The variation in the Mechanical properties (Tensile, Flexure and Impact strength) and morphological changes are studied.