本文在一个动态框架下,丰富了两阶段世代交叠模型(OLG),描述了最优退休年龄政策,并从出生率变化中分离出个体老龄化的影响。模型分析显示,在判断选择“延迟退休年龄”是否符合现实的最优选择时,主要取决于社会贴现率的发展态势。这个模型特别适用于去研究混合退休制度,在允许人们自由选择退休年龄的同时达到社会最优状态。这对我国政府在变革退休制度的政策制定上具有十分重要的理论价值和现实意义。 In a dynamic framework, this paper enriches the two-stage generation overlapping model (OLG), describes the optimal retirement age policy and separates the impact of individual aging from the birth rate change. Model analysis shows that judging whether the “delayed retirement age” meets the realistic optimal choice depends mainly on the development of the social discount rate. This model is particularly suitable for studying the hybrid retirement system, allowing people to freely choose the retirement age at the same time achieve the social optimum. This is of great theoretical and practical significance to our government in formulating the policy of reforming the retirement system.