From 1960's up to now, early retirement has been appearing to be a rarely consistent trend in the industrialized countries of the world; the participation of gerontic population in the labor force and the retirement age are being on the downside year by year. Along with the tendency of population aging and economic recession, early retirement is gradually turning from a social achievement to a social problem, and the questions as to when to retire and how much pension should be given are well worth rethinking in the geront-society. From the end of 1980's, the governments of the world started to review on the systems and undertake reforms in light of the early retirement trend. This thesis is grounded on the argumentation that institutional provisions will make influence on individual act; that is, the integral economic situation as well as the relevant retirement policies and plans of the government or of an enterprise will affect the retirement act of an individual. Therefore, this thesis is to probe, from the institutional aspect, the phenomenon of early retirement, the causative factors, the derivative problems, and the corresponding measures taken by each government facing the dual pressures from population aging as well as from early retirement.