Indium-Tin Oxide (ITO) thin films were deposited on the commercial glass substrate by rf-magnetron sputtering. The ITO films with the thickness of 2,000~2,400 $AA$ were prepared by changing the oxygen partial pressures of 2, 3, and 5%, as well as by changing the substrate temperature of $300^{circ}C$ and $500^{circ}C$. spectrophotometer, XRD, SEM, AFM, 4-point probe and Hall effect system were employed to characterize the ITO films. The optimum deposition conditions were the substrate temperature of $500^{circ}C$ and oxygen partial pressure of 2-3%. At theses conditions, the ITO film showed the transmittance of 91%, the resistivity of $5.4 imes10^{-3}Omega$cm, the carrier concentration of $1.0 imes10^{19} extrm{cm}^{-3}$, and the carrier mobility of 150$ extrm{cm}^2$/Vsec. In XRD spectra, the (222) and (400) $In_2O_3$ planes were dominant under the optimum deposition conditions When the substrate was cleaned only by the method of ultrasonic cleaning without both pre-annealing and chemical treatment of the substrate, the ITO film exhibited the transmittance of 86%, the carrier concentration of $5.4 imes10^{19} extrm{cm}^{-3}$ and the mobility of 24$ extrm{cm}^2$/Vsec.