Alot of studies on the associations between outdoor air pollution and effects on both acute and chronic mortality and hospital admissions have been published worldwide. The elderly population seems to be at a higher mortality and morbidity risk for air pollution. Time series studies based on Korean population show that elderly population are at higher risk of death due to nitrogen dioxide and Asian dust events. A study of daily hospital admission in Seoul shows that for ischemic heart disease the relative risk of admission associated with particle in the population aged 65 and more is two times higher that of younger population. APHEA (Air pollution on health; a European approach) projects show the similar trend of increased risk in elderly population. The effects of daily ambient particle concentrations on the number of deaths among the elderly in 28 European cities are consistently larger, by 10~20%, than those estimated for all age mortality. The mechanisms for the adverse health effects of air pollution have yet to be elucidated. A possible explanation is that air pollution adds the extra vulnerability which leads to increased risk of disease and morbidity. Regarding the fact that the proportion of elderly population has rapidly increased in Korea, we need to urgently lower the air pollution levels enough to protect the most sensitive populations including the elderly people.