Abstract: In view of the important role of government, enterprise and consumer in product quality regulation, the new pattern of coordinated regulation is put forward, which can make up the loopholes and improve the efficiency of government regulation. Based on that, the tripartite model of product quality regulation among government, enterprise and consumer is constructed to explore the mixed Nash equilibrium and action strategy. Then, using Matlab 7 analyzes the game model by substituting the actual data.
The results show that the factors that influence the government regulation behavior are the government's punishment to the illegal enterprise, the enterprise's compensation for the loss of the consumer, the cost of the qualified products and unqualified products. The production of qualified products is related to the cost of government regulation, the government's punishment, the direct and indirect economic losses caused by the production of substandard products. Cost of rights protection and compensation for consumers' losses are the main factors that affect consumers' strategic choice. Research also makes clear that the greater the probability of government regulation, the greater the probability of the production of qualified products; when the probability of consumer supervision becomes large, the probability of enterprises to produce qualified products also becomes large, and the probability of government regulation of the enterprise becomes small.
Finally, based on the perspective of government regulation, the measures to deal with the interests of all parties are given, the countermeasures and suggestions are put forward to ensure the quality of the products and to exert the advantages of the consumer supervision.

Key words: product quality, coordinated regulation, tripartite game, Nash equilibrium