National savings are critical capital resources to the economic development of a country. However, a poor economic performance and the deterioration of demographic condition can cause a reduction of national savings in a nation. Therefore, the intention of the study is to find out the relationships between economic and demographic influences on the national saving rate in Taiwan. Especially, the speed of the increase of aging population and the decrease of birth rate in Taiwan almost overpass the world. The study of the effect of the demographic factors on the national savings in Taiwan becomes importantly necessary. The economic data and demographic data are collected from Taiwan Economic Data Center (TEDC) Taiwan Economic Statistical Databank System from 1981 to 2000. The major findings are GNP, GNP per capita, Social Security payment, government spending, and aged dependency rate have a significant relationship with the national saving rate. The GNP, Social Security payment and aged dependency rate are negatively related to the national saving rate. The GNP per capita is positively related to the national rate.