Wood polymer composites based on untreated and maleic anhydride treated banana, hemp, and sisal fibers with HDPE resin are prepared in different ratios of 55:45, 50:50, 45:55, and 40:60 (wt/wt), respectively. Young's modulus and flexural modulus decrease with increase in fiber amount in the polymer. Maleic anhydride-treated fiber composites show highest Young's modulus and flexural modulus. The impact strength and shore-D hardness is also observed to be higher in maleic anhydride-treated fiber composites than in the untreated fiber composites.