The photocurrent created by the TiO 2 nanoporous film electrode modified by octadecanethiol(18SH) self-assembled monolayer(SAM) was found to be 1 95 times greater than that without modification as shown by cyclic voltammetry(CV). Meanwhile the maximum adsorbed peak has extended to the infrared range for about 20 nm. The formation of SAM was also assured with CV and small amplitude isosceles triangle potential methods, where the sensitization of SAM on the oxidation of CH 3OH on the TiO 2 nanoporous film electrode could be observed clearly. The results elucidated that the increased photocurrent by modification of octadecanethiol could not be simply attributed to the oxidation of octadecanethiol or ethanol. The results also implied that the application of SAM would be practicable in the sensitization of TiO 2 nanoporous film electrode in solar cell area.