ZnO with the wide band gap near 3.37 eV is typically an n-type semiconductor in which deviation from stoichiometry is electrically active. It was known that the films with a resistivity of the order of $10^{-4}{Omega}cm$ is not easy to obtain. In order to improve electrical characteristic of ZnO, we added 1, 3, 5 wt% Ga element in ZnO. The Ga-doped ZnO (GZO) was grown on a glass substrate by radio frequency (RF) magnetron sputtering at the temperature range from 100 to $500^{circ}C$. X-ray diffraction (XRD) patterns of GZO films showed preferable crystal orientation of (002) plane. The lowest resistivity of the GZO films was $8.9{ imes}10^{-4}{Omega}cm$. GZO films significantly influenced by the working temperature. The average transmittance of the films was over 80% in the visible ranges.