This study involves the synthesis of self-assembled gold nanoparticles (AuNPs) on the surface of ZnO nanorods as potential novel catalysts. ZnO nanorods were hydrothermally grown on an indum tin oxide (ITO) covered glass substrate containing an atomic layer deposited (ALD) ZnO seed layer over the ITO. Subsequently a layer of self-assembled AuNPs was formed on the surface of the ZnO nanorods. These AuNPs served as the active catalytic site for the catalytic probe reaction of reducing 4-nitrophenol (4-NP) into 4-aminophenol (4-AP). Catalytic behavior of the AuNP-coated ZnO nanorods was observed, indicating potential for use in various catalytic applications.