Fe-doped ZnO films were prepared on quartz glass substrates by sol-gel method, and the effects of different Fe-doped concentrations on the microstructure and optical properties of ZnO films were studied. X-ray diffraction was used to analyze the crystal orientation and crystal phase of thin film samples. The surface morphology of thin film samples was observed by atomic force microscopy, and the optical properties of znO thin film samples were analyzed by dual-beam UV-Vis spectrophotometer. The experimental results show that all ZnO film samples have hexagonal zinc structure, and ZnO grains grow optimally along the c-axis. After the incorporation of 1% fe with a mass fraction, the C-axis preference orientation of ZnO films was further enhanced, and the crystallization quality of the films was further improved. When the doping concentration of Fe is higher than 1%, the intensity of the diffraction peak of ZnO film (002) decreases, which may be due to Fe2+ (x=2 or 3) and zn2+ having different ion radii, and a large amount of Fe2+ enters the lattice to replace Zn2+, resulting in severe distortion of the lattice, thus affecting the normal growth of znO grains. The prepared ZnO films have high transmission abundance in the visible region, and the optical band gap of ZnO films estimated by the absorption edge shows that the optical band gap gradually widens with the increase of Fe doping concentration.