Objective: The study of stress oxidative as a pathogenic process in Down Syndrome (DS) patients is the goal of this paper. Methods: Explaining the mechanism of oxidative stress in DS, describing radical reactions to determine the type of free radical that can cause major damage, and the incidence of injury and studying strategies for coping with oxidative stress in DS are the issues considered in this paper. Conclusion: An increase in the expression of super oxide dismutase gene and mitochondrial dysfunction are the main factors in hydroxyl radical generation and oxidative stress in DS. Now, according to the studies done, a diet rich in fruit and vegetables based on taste desire of patient with DS along with regular physical activity are suggested as practical means to reduce oxidative stress in patients with DS.