The　surface　treatment　of　zinc　stannate　(Zn2SnO4)　film　for　use　in　dye-sensitized　solar　cells　has　been　carried　out　with　zinc　tin　oxide　precursor　solutions　through　chemical-bath　deposition　(CBD).　Mott　Schottky　measurements　demonstrate　that　the　flat　band　of　Zn2SnO4　has　a　moderate　positive　shift　owing　to　the　surface　treatment,　which　leads　to　a　slightly　decreased　V-oc.　Although　UV-vis　spectroscopy　reveals　that　the　adsorption　amounts　of　N719　and　D131　dyes　are　decreased,　EIS　results　and　OCVD　data　suggest　that　the　decreased　charge　recombination　rate　and　prolonged　electron　lifetime　give　rise　to　an　apparently　improved　efficiency　of　cells.　Consequently,　an　enhancement　of　13.5%　is　obtained　after　CBD　surface　treatment　under　the　illumination　of　one　sun　(AM　1.5,　100　mW　cm(-2)).