The idea of population balanced development is not new,however,there is a need to reach consensus by incorporating different arguments and theoretical discussion.The paper starts with the relationship between Chinese population flowing and building a population balanced society,and discuss two uestions: how to realize deep urbanization with the citizenization of the several hundred million peasant-workers;and how to achieve sustainable development of urban population,economy,society and resources when the several hundred million rural population rapidly entering into cities,finding jobs,and making livelihoods.The paper argues that the government will need to change development goals from passively controlling population size to actively building a population balanced society,from simply restricting the size of population to actively innovating social institution,and break through the stereotype of local population centered urban management and planning,and finally realize coordinated and balanced development between the size of urban population and its economy,society,resources,and environment.