本文之主要目的在探討全球人口老化趨勢與分析台灣人口老化所面臨之各種問題。要瞭解全球老化人口之趨勢，必須先分析開發國家與未開發國家地區之人口密度差別，各地區之人口爆發速度。蓋因世界人口將在2030年達到歷史上高峰，將有14兆(14 billion)之多，全球之出生率在1970年後開始下降減退。本文也要分析，「零人口成長」(Zero Population Growth)對於整個地球資源之分配影響，全球各地區之生命預期、死亡原因，全球各地區之人口年齡中數，以及老年與少年人口之比率等等主要人口特徵，才能透視全球老化人口之變遷趨勢與瞭解全球之社會資源、經濟生產，與生活資源之分配如何影響各地區之政治、經濟與社會問題。同時也可以觀察到人口數量之增減影響其年齡結構、性別、種族、與收入分配之變遷，這些人口特徵將會解釋為何全球各地與台灣之老化人口數目與比率增加之趨勢。

This paper intends to discuss the trends and characteristics of ageing population in the world and analyze the distribution of ageing population between the more-developed and the less-developed regions of the world. The first section presents the distribution of ageing population in the world and compare the fertility rate, mortality rate, median age, proportion of the young and the old, life-expectancy, population pyramids between the more-developed and the less-developed regions. The second section explores the trends of ageing population and the change of population structure in Taiwan. The factors of rapid increase in ageing population and the ageing speed are compared between the more-developed regions and Taiwan. The third section discusses the various social, economic, welfare, health care, and nursing care problems caused by the rapid ageing population. The conclusion recommends that professionals, scholars, governmental officers, and community leaders should take action in planning the effective national population policy, social security and pension policy, social welfare and health care policy as well as economic development policy to meet the challenges of "population explosion" in the near future.