This article investigated the effects and mechanisms of military service on health outcomes of Chinese elderly men aged 60 and older. While numerous studies explored the effect of military service on health in developed countries, we still knew little about the relationship between military service and later health outcomes in developing countries such as China. Using the data of China Health and Retirement Longitudinal Study, we found that military service is positively associated with better health outcomes of the elderly, in terms of physical health, cognitive abilities, and self-rated health. In addition, results of mechanism analysis show that, compared with nonveterans, elderly veterans had healthier habits, better education, higher individual and household income, and more favorable social medical security.Moreover, heterogeneity analysis indicates that this effect is more pronounced for older, rural, and spouseless elderly people. This article provided insights into elderly veterans’ health security measures in developing countries.