AbstractThe aim of this study was to investigate the decay resistance of wood- polypropylene composites (WPCs) treated with nano-zinc oxide against the white rot fungus Trametes versicolor and the brown rot fungus Coniophora puteana. WPCs containing different loadings of nano-zinc oxide, namely 0, 1, 2, and 3 percent (by weight), were made. The composites were subsequently exposed to a decay test according to a modified ASTM D1413 standard. Nano-zinc oxide distribution in the composite was studied by scanning electron microscopy (SEM) combined with energy dispersive analysis of X-rays (EDAX). No clear evidence of nano-zinc oxide agglomeration at a loading of 3% (w/w) was obtained using SEM-EDAX. The results showed that nano-zinc oxide improved the decay resistance of the composite against the fungi.