In this paper Cadmium oxide (CdO) thin films has attracted interest due to its potential applications in optoelectronics devices. thin films were grown on glass substrates by the pulsed laser deposition (PLD) technique at room temperature and different annealing temperatures Ta=(573,673 and 773) K. The structural studies (XRD) measurements for CdO thin film is polycrystalline with cubic structure and it is evident that the film is highly oriented in the (111) direction. Atomic force microscopy (AFM) was used to examine CdO surfaces, After annealing the films become more homogeneity and notice to increment the root mean square, surface roughness and average grain size. The optical properties of CdO thin films are studied as a function to wavelength in region (375 - 1100) nm. The optical transmittance of the prepared CdO films notice that the transmittance pattern of all deposited thin films increases with increasing the annealing temperature (Ta). The direct energy gap for CdO films was decreases with increasing of annealing temperature for all samples due to the growth of the crystallites .The optical constants such as refractive index, extinction coefficient and dielectric constant were also calculated.