Highly transparent N-doped ZnO thin films were deposited on ITO coated corning glass substrate by sol–gel method. Ammonium nitrate was used as a dopant source of N with varying the doping concentration 0, 0.5, 1.0, 2.0 and 3.0at%. The DSC analysis of prepared NZO sols is observed a phase transition at 150°C. X-ray diffraction pattern showed the preferred (002) peak of ZnO, which was deteriorated with increased N concentrations. The transmittance of NZO thin films was observed to be ~88%. The bandgap of NZO thin films increased from 3.28 to 3.70eV with increased N concentration from 0 to 3at%. The maximum carrier concentration 8.36×1017cm−3 and minimum resistivity 1.64Ωcm was observed for 3at% N doped ZnO thin films deposited on glass substrate. These highly transparent ZnO thin films can be used as a window layer in solar cells and optoelectronic devices.