Abstract: To study on the impact of government regulation on differential pricing of asymmetric information in closed loop supply chain, three stage game model is constructed which is composed of government, manufacturer, retailer and consumers and analyze the optimal pricing strategy under government subsidies and punishment policy.Results show that:the optimal level of regulation by the government,asymmetric information of external costs per unit of product changes on manufacturers' profits is more significant; there exists a point of new and remanufactured replacement rate,which has a different effect on retailer pricing ofthe two decisions;the social welfare is a joint convex function of government regulation, and there is an optimum level existing in government's rewards and punishments, which increases the level of government control and plays a positive role for manufacturer to improve production processes and facilitates recovery levels.

Key words: government regulations, Closed-Loop Supply Chain, asymmetric information, differential pricing, Game Theory