本文以全臺360個鄉鎮市區為分析單位，探討1970-1990年間人口老化空間之變遷與特性。首先，藉著不同時期各地平均年齡、老年人口百分比及老化指數跨越人口老化臨界值的空間分布，探究其空間變遷過程。其次，分析人口老化主導要素-生育下降與遷移的時空演變。最後，並找出此兩要素如何形塑人口老化區域特性。 分析結果如下：人口老化跡象較早顯著者，俱屬位置偏遠或經濟發展條件不利的地區（例如：竹苗丘凌及其東南山地區、中央山脈西南側丘陵），並由這些地區逐步向外擴散。總生育率（TFR）的降幅在八○年代較大，並且已有半數以上鄉鎮市區降低到替代水準（TFR=2.1）之下，其空間擴散途徑，源於大都來，漸及次級都市，最後擴及鄉村地區。大都會及工業區長期以來，一直是移入主要目的地，也是淨遷移率為正值的地區。因此，臺灣地區人口老化可分成「移出而老化加速」、「移入而老化緩和」與「移入而老化加速」三型，以分布於鄉村地區的第一類型，老化最嚴重；第二類型以都市地區為主；第三類型僅在具大型榮家之地出現。

　　　　　The focus of this study is on the spatial changes and characteristics of population aging between 1970 and 1990 based on the 360 districts of townships (Country, Town, City and District) as units of analysis. First, the process of spatial changes was investigated based on the different stages of the mean age, the percentage of old people and the aging index over through the critical point. Second, the main factor of population aging which including decrease in the birth rate and historical changes of migration would be analysed. Finally, the reason for which the regional characteristics of aging was made by the above two factors would be given. The results are as follows: Population aging occurs first in the rural or economically undeveloped areas, e.g. the hills of Hsinchu-Miaoli and its southeastern part areas, and the southwestern hills of Central Mountains. The way of diffusion is from the above areas outward to neighbouring townships, then to some big cities. The decrease oft he total fertility rate (TFR) was larger in the eighties and the value of TFR was below replacement level in over half of the townships. The diffused direction of TFR is opposite to the above, from the metropolitan or big cities, then the small cities and finally, the countryside. However, metropolitan and industrial areas are the places of immigration and also with the positive net migration rates. There are three types of population aging in Taiwan: <Progressive aging through emigration>, <Decreased aging through immigration>, and <Progressive aging through immigration>. The first type is most serious in rural areas, the second in metropolitan areas, and the third among areas with high numbers of veteran homes.