Abstract: Based on the Marxist theory of "two kinds of production" and drawing on related theories, this paper demonstrated the theoretical basis and internal logic of the fertility support policies; it also analyzed the practical basis for the construction of the fertility support policy in the light of the demographics, economy, society and resource-environmental realities of contemporary China. The study found that: (1) sustained low fertility is an inevitable trend in the development of human society and a common law existing in the process of economic and social modernization. (2) The essence of fertility is labor, and it is an important part of the total labor of society. Therefore, the direct and indirect support for fertility is determined by the nature of fertility. (3) Formulating fertility support policies should be based on the Marxist "two kinds of production" principle as the theoretical basis and guiding ideology. (4) The construction and improvement of the fertility support policies system must be integrated with China's objective reality. Finally, relevant policies considerations on the construction of the fertility support policies were made: first, to gradually improve and perfect the fertility support policies from a practical point of view; second, to make a good top-level design and provide institutional and mechanism safeguards for the fertility support policies; third, to attach great importance to the synergy between the fertility support policies and other social and economic policies; and fourth, to make efforts to alleviate the burden of childbearing on individuals and families, and to reduce the economic and non-economic costs of childbearing.