The effects of various buffer layers on the In2O3 transparent conducting films grown on glass substrates by radio-frequency reactive magnetron sputtering were investigated. The In2O3 thin films were deposited at 400℃ of growth temperature and 100% of oxygen flow rate. The optical, electrical, and structural and morphological properties of the In2O3 thin films subjected to buffer layers were examined by using ultraviolet-visible spectrophotometer, Hall-effect measurements, and X-ray diffractometer, respectively. The properties of In2O3 thin films showed different results, depending on the type of buffer layer. As for the In2O3 thin film deposited on ZnO buffer layer, the average transmittance was 89% and the electrical resistivity was 7.4×10-3 Ωcm. The experimental results provide a way for growing the transparent conducting film with the optimum condition by using an appropriate buffer layer.