The Cadmium sulfide (CdS) is the most advantageous material for the manufacture of the elaborate solar cells in thin layers, the study that we present, will relate to the elaborated and the characterization of CdS thin film deposited on glass substrates by chemical bath deposition (CBD) method. This study will help us to know if the annealing atmosphere nature affects the deposition of thin films of CdS. The X-ray diffraction (XRD) analysis reveals that the structures of pure thin films are Hexagonal and polycrystalline with preferential orientation (002). The scanning electron microscopy (SEM) measurements showed that the surface morphology homogeneous and uniform. The energy dispersive X-ray analysis (EDAX) studies confirmed that the films are nearly stoichiometric. The transmittance in the visible region (200-800 nm) is high of 60%, and band gap values oscillated between 2.36 and 2.47 eV for al thin films.