This paper describes a novel chemical method for controlled assembly of regular composite nanowire arrays at the molecular level. The polycationic poly(N-vinylcarbazole) (PNVK) template is prepared by electrochemical polymerization of the N-vinylcarbazole monomer. Regular composite nanowire arrays of thallic oxide (Tl2O3) and polycationic PNVK are fabricated through ordered aggregation of the negative Tl2O3 nanoparticles along the positive chains of the polycationic PNVK in the polycationic PNVK-arachidic acid (AA) mixed monolayer on the air-alkaline Tl2O3 sol interface. The widths of the Tl2O3 and the polycationic PNVK nanowires are 3.2 and 2.7 nm, respectively. The above regular nanowire arrays can also be obtained when a polycationic PNVK single component is used as a template. These nanowires lie in the plane of the corresponding monolayers. The polycationic PNVK-AA mixed monolayer and the Tl2O3 nanowire arrays aggregated along the polycationic PNVK chains can be easily transferred onto hydrophobic substrates layer by layer to form Langmuir-Blodgett (LB) multilayers with a spacing of 5.5 nm. This novel method should be applicable to the preparation of a wide range of composite nanowire arrays.