A composite of poly(3-hexylthiophene) (P3HT) grafted on TiO2 nanotubes was synthesized. it was characterized using XRD, TEM, TGA, FFIR and XPS. Cyclic voltammetry (CV) was used to elucidate the electrochemical behavior and evaluate the HOMO and LUMO energy levels. Photoluminescence (PL) measurements show that the emission intensity of P3HT mixed with TiO2 nanotubes was one third of that of random P3HT, while that of P3HT grafted onto TiO2 nanotubes was 10% of random P3HT. The results show that the P3HT grafted onto TiO2 nanotubes is more efficient in photoinduced charge transfer than a physical mixture of P3HT and TiO2 nanotubes, indicating this composite has potential for the fabricating hybrid organic-inorganic solid state solar cells. Crown Copyright (C) 2009 Published by Elsevier Inc. All rights reserved.