Superhydrophobic films were developed on wood substrates with a wet chemical approach. Growth of zinc oxide (ZnO) nanorods was found differentially in the cross-sectional walls and inner lumenal surfaces. The surface roughness of the prepared films on the inner lumenal surface conformed to the Cassie-Baxter wetting model, whereas the roughness across the microsurface of the cell wall was in conformity with the hydrophobic porous wetting model. The space between the ZnO nanorods and the microstructure of the wood surface constituted the nanoscale and microscale roughness of the ZnO nanofilm, respectively. The water contact angle of the prepared wood surfaces was up to 153.5 degrees. In the prepared films, monolayers of stearic acid molecules were self-assembled on the ZnO nanorods, which in turn, were attached to the wood surface via dimeric bonds. VC 2010 Wiley Periodicals, Inc. J Appl Polym Sci 119: 1667-1672, 2011