Here, we demonstrate that the introduction of the monodispersed nanoparticles into photoelectrode materials can obviously improve the photovoltaic performance of dye-sensitized solar cells (DSSCs). The highly transparent dispersions of TiO2 and Ag nanoparticles with the excellent stability were synthesized respectively. As seed crystals, monodispersed TiO2 nanoparticles with the diameter of about 5 nm have unique advantages in regulating the growth of multi-branched TiO2 nanowire arrays (T-MB-TiO2), which have large specific area. Ag nanoparticles monodispersed in n-hexane with a small particle size (about 8 nm of average diameter) were incorporated into above-mentioned T-MB-TiO2 to fabricate the T-MB-TiO2/Ag composite photoanode, which combines the advantages of T-MB-TiO2 with the direct electron transport channels and Ag nanoparticles with the localized surface plasmon resonance effect. Therefore, the DSSCs with the composite photoanode achieved excellent photoelectric performance, as high as the short-circuit current density (Jsc) of 24 mA/cm2 and the photoelectric conversion efficiency (PCE) of 10%. Compared with the cell assembled by the photoanode of pure TiO2 nanowire arrays grown on the FTO glass directly, Jsc and PCE of the cell with T-MB-TiO2/Ag composite photoanode has been increased by 48% and 28% respectively, which has a great application potential in the fields of solar cells and photocatalysis.