Sn-doped gallium oxide (Ga2O3:Sn) films were deposited on beta-Ga2O3 (100) substrates by metal organic chemical vapor deposition method. The Sn concentration was varied from 1 to 12 % (atomic ratio). The influences of Sn-doping concentration on structure, raman, and photoelectric properties of the films were investigated in detail. The obtained films were monoclinic beta-Ga2O3 homoepitaxial films. A decrease of about eight orders of magnitude in the film resistivity could be achieved through Sn doping. The 10 % Sn-doped film exhibited the best electrical properties and the lowest resistivity of about 1.20 x 10(-1) Omega cm, with the hall mobility value of 12.03 cm(2) V-1 s(-1)obtained. The average transmittances of the beta-Ga2O3: Sn films in the visible and UV wavelength ranges were all over 85 %. The optical band gap of the films with different Sn-doping concentrations could be modulated from 4.16 to 4.69 eV.