The mechanical properties and water absorption of low-density polyethylene/ sawdust composites were investigated. The relationship between the filler content and the composite properties was also studied. Different degrees of esterification of the sawdust with maleic anhydride were obtained with different reaction times. The experimental results demonstrated that the treatment of sawdust by maleic anhydride enhanced the tensile and flexural strengths. The water absorption for maleic anhydride treated sawdust indicated that it was more hydrophobic than untreated sawdust. The effects of the addition of benzoyl peroxide during the preparation of composite samples on the water absorption and mechanical properties were also evaluated. (C) 2007 Wiley Periodicals, Inc.