Transparent and conductive thin films of multicomponent oxides composed of binary and/or ternary compounds with varied chemical compositions have been prepared by rf or dc magnetron sputtering. Transparent conducting oxide (TCO) films were prepared in multicomponent oxides composed of ZnO, SnO2, Ga2O3, or MgO combined with In2O3, or ZnO combined with SnO2, containing ternary compounds such as Zn2In2O5, In4Sn3O12, GaInO3, MgIn2O4, and ZnSnO3. In addition, the TCO films were prepared in a multicomponent oxide composed of combinations of these ternary compounds. In particular, the Zn2In2O5 and In4Sn3O12 films exhibited a resistivity of 2 x 10(-4) Omega cm, comparable to that of indium-tin-oxide films. TCO films could always be obtained in multicomponent oxides consisting of combinations of metal oxides as long as these oxides were TCO film materials or transparent conductors; the mixture ratio of the components could be varied over all possible compositions. The electrical, optical, and chemical properties, the band-gap energy, and the work function of these. transparent conducting multicomponent oxide films could be controlled by changing the composition. Consequently, transparent conducting multicomponent oxide films are suitable for specialized applications because their electrical, optical, and chemical. properties as well as physical properties can be controlled by altering the chemical composition.