Ti-Ga co-doped ZnO thin films (TGZO) have been successfully prepared on glass substrates by DC magnetron sputtering at room temperature. The X-ray diffraction (XRD) patterns show that all the deposited films are polycrystalline with a hexagonal structure and have a preferred orientation along the c-axis perpendicular to the substrate. The distance between target and substrate was varied from 41 to 75 mm. The crystallinity increases obviously and the electrical resistivity decreases when the distance between target and substrate decreases from 75 to 46 mm. However, as the distance decreases further, the electrical resistivity increases. It is obtained that the lowest resistivity is 2.0610-4cm when the distance between target and substrate is 46 mm. In the visible region, the TGZO films show a high average transmittance of above 90 %.