The objective of this study was the deposition of thin films of 8-hydroxyquinolin (8-HQ) Cobalt(II) and Nickel(II) complexes onto glass substrates using the chemical bath deposition (CBD) method. The deposition experiments were carried out under the effect of some physicochemical factors such as solution temperature (25 °C–55 °C), medium pH (1–6), metal: ligand molar stoichiometric ratio (1:1–1:3), and immersion time (in the range 10–60 min). The obtained thin films were characterized using many analytical methods (UV-Vis spectrophotometry, infrared spectrophotometry, optical microscopy, scanning electron microscopy, and X-ray diffraction). The study of the optical properties of the obtained thin films showed that the complexes [Ni(8-HQ)2(H2O)2] and [Co(8-HQ)2(H2O)2] have strong absorbance in UV area corresponding to a π-π* or n-π* electronic transition between the HOMO and the LUMO with a gap’s energy in the range 4.1 and 4.4 eV. In the light of the optical measurements, [Ni(8-HQ)2(H2O)2] and [Co(8-HQ)2(H2O)2] complexes can be considered as semiconductors.