A photoanode composed of homogeneously dispersed Au nanoparticles (NPs) within TiO2 mesoporous film (TiO2/Au) was fabricated via an in situ assembly process for plasmon-enhanced CdS/CdSe quantum dot sensitized solar cells (QDSCs). The incorporation of Au NPs in the photoanode for QDSCs shows improvement not only in the photocurrent density with increased photon capturing but also in photovoltage arising from reduced charge recombination. TiO2/Au based photocanode exhibits excellent injection and transport efficiency of photoinduced charge carriers, which likely arose from the core-shell structure of CdS and CdSe QDs assembled on the surface of Au NPs, preventing Au NPs from contacting directly with electrolyte. As a result, the power conversion efficiency of the QDSCs with TiO2/Au photoelectrodes reached 6.00%, which is about 50% enhancement of the efficiency for the solar cells without Au NPs (4.04%).