Background and Aims: Newcastle disease (ND) is one of the most serious illnesses of chickens. Live vaccines are widely used to prevent chicken from the disease all over the world. Materials and Methods: To access the effective and potentiate ND vaccine, a homogenous subpopulation from LaSota strain was selected following cultivation of the virus on primary chicken embryofibroblast (CEF) cells. Pathogenicity indices and molecular characterization of a several plaques at 3rd passage were analyzed and then the selected clone was candidate for vaccine development. ND vaccine was prepared according to the standard protocols. Results: The immunogenicity of the live vaccine was examined in specific pathogen free (SPF) and commercial chickens. The geometric mean hemagglutination-inhibition (HI) titers induced in chickens vaccinated with the cloned vaccine were not significantly differ than those induced in chickens vaccinated with the similar ND clone vaccine. Conclusion: Efficacy of the ND vaccine was estimated against the virus challenge. The results indicate that the cloned vaccine could confer a complete protection against NDV.