Indium tin oxide(ITO) thin film was deposited at room temperature on polycarbonate(PC) substrate by in-line sputter system. ITO sputtering process was carried out at a various pressure for the reduction of ion damage on PC substrate and the electrical and the optical properties of deposited ITO films were obtained and analyzed. From the experimental results, the sheet resistances of as-deposited ITO films varied with a different pressure and the optical transmittances at visible wavelength were maintained above 85%. The results are considered to be related to the pressure of oxygen atoms as a reaction gas.