Abstract: The adjustment of China’s family planning policy has aroused great concern in society, and it is particularly important to scientifically evaluate the effect of policy implementation. This paper uses the 2001 Family Planning Law to advocate a couple having two children as a quasi-natural experiment, based on the provincial annual panel data from 1982 to 2013, this paper uses the panel and panel threshold model to explore the effectiveness and mechanism of the implementation of the family planning policy. The empirical results show that: First, the family planning policy is significantly positively related to the birth rate of the population at the level of 10%; The crossover term between the family planning policy and the socialization of fertility costs is significantly positively related to the Fertility Ratio at the 10% level. This indicates that the family planning policy is effective and can improve the Fertility Ratio. Besides, the more the socialization of cost transfers, the higher the Fertility Ratio is. From the perspective of regional grouping, the policy effectiveness of the eastern and central regions is stronger. Second, from the perspective of parameter estimates, compared with low-house housing areas, the more obvious the policy effect is in high-housing areas; compared with low-literate groups, the more obvious the policy effect of high-literacy groups.

Key words: the family planning policy, socialization of fertility costs, policy evaluation