Ion irradiation can be used to modify the physical properties of optoelectronic materials in well defined regions and consequently, to produce integrated circuits in surface layers. In most cases, the change of physical properties such as the refractive index, the absorption coefficient, the density and the conductivity are strongly influenced by the radiation damage which is caused by the ion implantation process. So, the study of the generation, transformation and annealing of radiation defects as their connection with the physical properties of the materials is very important. A review of the effect of radiation damage on the properties of essential optoelectronic materials as SiO2and LiNbO3will be given in this paper. It deals mainly with the mechanism of defect generation, the annealing of defects by thermal treatment and the optical properties of materials affected with defects.