The properties of molybdenum-doped ZnO (MZO) films deposited by radio-frequency (rf) magnetron sputtering and organic light-emitting devices (OLEDs) using an MZO film as an anode were investigated. A transparent conducting MZO film with high transparency and relatively low resistivity was prepared by rf magnetron sputtering at room temperature. The structural, electrical, and optical properties of the films deposited under different Ar pressures were investigated. X-ray diffraction patterns showed that the nature of the films is polycrystalline with a hexagonal structure and a preferred orientation along the c axis. Thus, MZO films may be a potential material for OLEDs.