Abstract: The DC magnetron sputtering process of ITO target was studied. The optimal process parameters were determined by orthogonal test method, and the effects of sputtering temperature, oxygen-argon ratio, sputtering pressure and sputtering power density on resistivity and visible light transmittance of ITO films were investigated. The optimal sputtering temperature was 370 ℃,the optimal oxygen-argon ratio 0.5/40, the optimal sputtering pressure 0.4 Pa, and the optimal sputtering power density 0.17 W/cm². The resistivity of ITO films was affected by various factors, the order of priority was oxygen-argon ratio, sputtering temperature, sputtering pressure and sputtering power density. The priority order of factors affecting the visible light transmittance of ITO films was sputtering temperature, sputtering pressure, oxygen-argon ratio and sputtering power density.