Abstract: Starting from the matching relationship between the focus of government attention allocation and the evolution characteristics of public policy,it is identified that under the action of continuous,shifting,fluctuating and supportive government attention,the policy process presents four patterns -policy balance,discontinuity,fragmentation and iteration.At the same time,taking China's fertility policy as an example,this paper studies the matching relationship between the government attention and China's fertility policy.It is found that the switching relationship among the four policy patterns accords with the spiral law from policy discontinuity to re-equilibrium,and the allocation of government attention is easy to evolve into a screening mechanism for policy issues,thus the phenomenon of "signal filtering" and "information exclusion" is produced;the inherent idea and the relatively stable policy framework strengthen the bluntness of the shift of attention,and the policy equilibrium is kept constant;the policy elite is guiding the government's vision,which is not separated from the scope of the initiative,playing a key role in promoting the transformation of policy patterns instead of an indirect role in the formation of policies.The study attempts to clarify the matching relationship between differentiated allocation of government attention and public policy patterns,and themechanism of the dynamic adjustment of government attention resources on policy practice,which is of positive significance to understand the formation and evolution process of public policy patterns.

Key words: allocation of government attention, differentiation, policy change, policy modality, China's fertility policy