gamma-FeOOH thin films were produced by Chemical Bath Deposition (CBD) method at pH: 5 onto amorphous glass substrates. Structural properties of gamma-FeOOH thin film were analyzed with X-ray diffraction (XRD). Chemical analysis and surface image of thin film were investigated with EDX, SEM, respectively. Optical properties were investigated via UV-VIS spectrophotometer. gamma-FeOOH (lepidocrocite) crystal is orthorhombic structure and the XRD peak corresponding to the gamma-FeOOH is enhanced to (1 1 1) plane. The allowed direct and allowed indirect optical band gaps (Eg), optical transmission (T%), reflectivity (R%), absorption, refraction index (n), extinction coefficient (k), dielectric constant (epsilon) of the thin film were found to be 2.00 and 1.63 eV, 36.39 %, 24.86 %, 0.43, 2.98, 0.03 and 1.76, respectively.