For the synthesis of cadmium sulfide (CdS) nanoparticles, microwave assisted solvothermal method with ethylene glycol as the solvent was used in this work. The cadmium acetate and thioacetamide were used as the cadmium source and sulphide source. Semiconductor nano particles doped with transition metal ions have attracted wide attention due to their excellent luminescent properties. The nano-structured materials of CdS prepared with different annealing periods were characterized by XRD method. The size of the crystallites were determined by XRD method to be 10 nm depending on the amount of the molar ratio of the reactants. The effect of different annealing temperature, concentration of dopants and ionic radii of dopants are also studied.