Dye-sensitized Solar Cell (DSC) reported by M. Graetzel in 1991 promised easy, low-cost fabrication compared with the conventional photovoltaic solar cell. DSC achieved high photon-electron conversion efficiency because the dye adsorbed semiconductor electrode (mostly TiO₂) with the dye adsorbed absorbs light and generates electricity by that external quantum efficiency. The single ideal dye in a DSC should absorb all visible light and smoothly transfer electrons to the TiO₂ electrode, but this ideal dye has not yet been developed. The problem is that using a single dye with a long wavelength, it is difficult to inject electrons from the dye to TiO₂ electrode because the LUMO of the dye approximates the conduction band of TiO₂. But if a mixture of dyes with different wavelengths is used, it is still difficult to inject electrons from the dyes because the electron transfer would occur between the dyes. Here we show a DSC using novel dye system to achieve high external quantum efficiency as sensitizers.