The reticular hierarchical structure of butterfly wings (Papilio Paris) is introduced as template for Au/TiO2 photocatalyst by depositing the Au nanoparticles on TiO2 matrix, which is carried out by a water-ethanol sol-gel procedure combined with subsequent calcination. The obtained Au/TiO2 nanocomposites present the reticular hierarchical structure of butterfly wings, and Au nanoparticles with an average size of 7 nm are homogeneously dispersed in TiO2 substrate. Benefiting from such unique reticular hierarchical structure and composition, the biomorphic Au/TiO2 exhibits high-harvesting capability and presents superior photocatalytic activity. Especially, the biomorphic Au/TiO2 at the nominal content of gold to titanium of 8 wt% shows the highest photocatalytic activity and can completely decompose methyl orange within 80 min, which is obviously higher than that of commercial Degussa P25 powders. (C) 2011 Elsevier Inc. All rights reserved.