Effect of chemical corrosion on the tensile strengths of five types of Bangladeshi timbers (kadom, simul, koroi, mango, and debdaro) and their composites has been evaluated. Wood-plastic composites (WPC) formed by the gamma-radiation induction polymerization of butylmethacrylate (BMA) with those timbers show better resistance to chemical corrosion attack than the parent timbers. Enhanced mechanical properties such as tensile strength of the composites are also protected during corrosion.