In this paper, indium tin oxide/silver indium/indium tin oxide (ITO/AgIn/ITO) composite films were deposited on glass substrates by magnetron sputtering. The effects of the sputtering temperature on the optical and electrical properties of the composite films were systematically investigated. The ITO/AgIn/ITO composite films deposited at sputtering temperatures of 25 °C and 100 °C demonstrated a high reflectivity of 95.3% at 550 nm and a resistivity of about 6.8–7.3 μΩ·cm. As the sputtering temperature increased, the reflectivity decreased and the resistivity increased slightly. The close connection between microstructure and surface morphology and the optical and electrical properties of the composite films was further illustrated by scanning electron microscopy imaging and atomic force microscopy imaging. It is shown that the ITO/AgIn/ITO thin films have a promising application for high-reflectivity anodes.