This study investigated the applicability of single wall carbon nanotubes (SWCNT) with the functional group deposited on the FTO-glass (Fluorine doped tin oxide. SnO2:F) substrate of the counter electrode for a dye-sensitized solar cell (DSSC). A nanocrystalline TiO2 layer was fabricated on the FTO-glass substrate of the working electrode, and then sintered in a high-temperature furnace. The working electrode with a TiO2 thin film was immersed in the solution of N-719 (Ruthenium). dye for 12 h. Moreover, the counter electrode with a layer of Ag (or without a layer of Ag) and a layer of SWCNT, which were (or was) fabricated in that order on the FTO-glass substrate, was subsequently prepared. Finally, the DSSC was assembled, the power conversion efficiency of the DSSC was measured using an I-V measurement system, and the incident photo conversion efficiency (IPCE) of the DSSC was obtained using the phase-locked loop optical chopper. This study also examined the effects of a layer of Ag deposited on the FTO-glass substrate, the type of organic solvent (such as DMAC and acetylacetone), and the sintering temperature on the performance of the DSSC. This film of SWCNT/Ag markedly increased the IPCE from 3.9% (conventional DSSC with a thin film of platinum on the FTO-glass substrate of the counter electrode) to 15.3% (DSSC with SWCNT/Ag/acetylacetone), as the wavelength of the light was 380 nm. Furthermore, as the wavelength of the light is 550 nm, the IPCE of the DSSC with SWCNT/Ag/acetylacetone (6.8%) becomes nearly equal to that of conventional DSSC (7.2%). Most interestingly, this study shows that the power conversion efficiency of the DSSC with SWCNT/Ag/acetylacetone (1.3037%) is not inferior to that of DSSC with a thin film of platinum on the counter electrode (1.25%). Crown Copyright (c) 2010 Published by Elsevier B.V. on behalf of The Society of Powder Technology Japan. All rights reserved.