It is widely known that population has a considerable impact on socioeconomic development. Conversely, the direct or indirect influence of development on population change is generally neglected. Such negligence prevents people from a correct understanding of the mechanisms governing population change, and therefore leads to incorrect understanding of policy options. Demographic transition in China has already entered a period of ‘low fertility and low mortality.’ Population policies should be seen in the framework of long-term sustainable development and options should be considered accordingly. This chapter primarily focuses on the decisive influence of socioeconomic development on demographic transitions, the general pattern and the stage of China’s demographic transition, as well as the economic, social, and policy factors that are impelling China’s demographic transition.