為探討臺灣民眾退休不足度，本研究不同以往問卷式詢問臺灣民眾準備狀況，使用所得替代率(replacement rate)為工具，建構估算模型，透過宏利人壽委託政大民調中心進行的民調數據，實際估算勞工與軍公教民眾退休不足度，其中發現台灣有24%勞工民眾在退休後無法達到60%所得替代率，且低估死亡時間與高估報酬率都會對勞工退休不足度造成影響。而對軍公教民眾而言，以80%所得替代率進行估算，才會有退休不足的問題，而低估死亡時間與高估報酬率對退休不足影響較小。此外探討退休信心與實際估算不一致的情況，主要發現高所得的勞工民眾，較可能發生有信心但準備不足60%所得替代率的情況，而低所得的勞工民眾，較可能發生沒有信心但可以準備80%所得替代率的情況，本研究認為是因為臺灣現行退休金制度下，高所得的勞工民眾若要達到相同所得替代率，所需儲蓄率高於低所得的勞工民眾。 / The purpose of this paper is to examine the Retirement Shortfall in Taiwan by using replacement rate. Building model with the poll data which is commissioned by Manulife Life Insurance and conducted by Market Survey Research Center of National Chengchi University, we found that the populations of the civil servants can achieve 60% replacement rate after retirement, but 24 percent of labors can’t reach the 60% income replacement rate. Besides, the retirement shortfall of labors become worse after adjusting by the overestimate of rate of return and underestimate of longevity risk. In short, labor people should contribute more to their pension in case they may have inadequate retirement situation. Using logistic regression, we found that people of high-income have tendency to feel overly optimistic of their retirement shortfall, vice versa. Social security and pension benefit provide less replacement rate for people of high-income, so rich people need highly save rate.