Abstract: The public policy formulation is a progress of the interaction between government and civil.Rational choice institutionalism is an approach of introducing the concept of Actor and Action Arena to analyze the behaviors under the given institutional situation,which can be used to analyze the interaction between government and civil. The key to construct the interactive model between government and civil in public policy formulation is broadening channels of the interaction between government and civil,constructing diversified interest-inputting mechanism; realizing the reutilization of public policy formulation; ensuring the normalization of the interaction by utilizing the institutionalization,establishing and perfecting the system of laws and regulations.