In this letter, modifications of (10,0) functionalized zigzag Single-Wall Carbon Nanotubes in different sites by thiophene groups were studied using density functional theory. Geometric structures and electronic properties were investigated. After modification a significant change was observed in band structure and density of states and metallic properties were obtained. The best result for application in organic photovoltaic cells was achieved when two organic groups were placed on opposite sides of the wall of the SWCNT symmetrically. (c) 2013 Elsevier B.V. All rights reserved.