In research on alternative photoanode materials for dye-sensitized solar cells (DSCs), there is rarely any report on WO3, probably due to its acidic surface and more positive (vs NHE) conduction band edge position compared to TiO2 and ZnO. For the first time, dye-sensitized solar cells based on porous WO3 nanoparticle films were successfully fabricated with efficiency of up to 0.75%. The multicrystalline structure of WO3 was examined by Raman spectroscopy and X-ray diffraction analysis. It was found that significant performance enhancement can be obtained from treating the WO3 nanoparticle film with TiCl4; the TiCl4-treated WO3 DSCs were recorded with efficiency reaching 1.46%.