Abstract: The Third Plenary Session of the Twentieth Central Committee of the Communist Party of China proposed that the common prosperity of all people should make more tangible and substantial progress.The period from now to 2035 is a critical one for China to make substantial progress in promoting common prosperity,and it is also an important period of transition in Chins population development,and the new trends in Chinas population development will have a greater impact on the promotion of common prosperity.In terms of enlarging the “cake”,the huge population size provides huge potential for industrial development and technological innovation,and the concentration of population in urban agglomerations and big cities can bring about a scale effect and thus promote economic growth.However,the aging of the population will lead to problems such as insufficient supply of labour and a decrease in total factor productivity,which will pose challenges to economic growth.In terms of sharing the “cake”,the large size of the population makes it more difficult to “raise the low”,“expand the medium” and “raise the high”.Rapid population aging and the huge size of the elderly population will bring challenges to the common prosperity of the elderly group,artificial intelligence to solve the aging problem may lead to widening income disparity at the same time,the decline in economic vitality of the outflow places caused by population contraction will lead to widening regional development gap,and the super-large-scale mobile population will increase the difficulty of expanding the middle-income group.Therefore,on the one hand,it is necessary to give full play to multi-dimensional demographic dividends such as the scale dividend,quality dividend and allocation dividend to hedge against the impact of demographic transition and to enlarge the “cake”;on the other hand,it is necessary to optimize the three-tier distribution system based on the new trend of demographic development and to share the “cake” well.

Key words: population development, common prosperity, public policy