Abstract: Based on realistic parameters, the simulation finds that delayed retirement not only does not crowd the welfare of the working population, but instead improves the welfare of the working population, and this result is stable for the changes in the parameters and the pension system, and the mechanism is that the delay in retirement increases the per capita output and reduces the burden on the working population. In turn, the welfare level of the working population will be improved. The policy inspiration of the article is to publicize and convey this fact to the public, and to provide a delayed retirement plan as soon as possible in response to the post-60 baby boom. However, it is appropriate to control the rise in fertility costs and pension replacement rates, which can ensure the future delayed retirement plan will not reduce the welfare of the working population.

Key words: delayed retirement, labor population welfare, dynamic optimization, defined benefits, defined contribution