The natural environment plays an important role not only in ecological sustainability, but also in human health. Growing attention has been focused on the health benefits of natural environments with increasing scientific evidence in this field. Urban green space has positive effects on individual and community health; thus, it is considered as social infrastructure. The natural environment promotes mental health by relieving psychological stress and depression. Physical health can be improved by experiencing nature, which reduces physiological stress and boosts the immune system. Several international initiatives have been undertaken to improve our understanding in this field and to utilize these benefits for health promotion. Interdisciplinary approaches are needed to promote human health through the natural environment in the fields of science, education, planning and policy.