From the perspective of social welfare maximization, a product life cycle model involving both producers and consumers was built in which the regulation standards for both recycling and reducing were determined, and the major factors affecting the optimal standards were discussed. The results showed that the socially optimal condition is reached when the value of each marginal product equals its net price, and the recycling cost, input's marginal contribution, price of material input, cost of waste disposal are the most important factors for the optimal standards. Therefore, in order to maximize the social welfare, policy makers should take both environmental and economic performances into account while making EPR (extended producer responsibility) regulation policies.