Abstract: In this paper, Stackelberg dynamic game model is constructed and how to make a products quality control strategy when the supplier and retailer self-build and entrusting a third party builds the internet channel is analyzed. How the market proportion, supplier's profit sharing ratio, the demand price elasticity and quality cost function affect products quality control strategy in mixed distribution channel, and further influence the demand of retailing channel and internet channel, the expected profits function and consumers surplus are analyzed. The model analysis demonstrates that:with the increasing of retailing channel market proportion, the products quality level when the supplier self-builds the internet channel will be higher than that when entrusting a third party builds the interner channel and also higher than retailer self-builds the interner channel; when the supplier self-builds internet channel, the products quality level and supplier's expected profits will decrease firstly and then increase, namely U-shape; when the retailer self-builds internet channel, the demand of retailing channel and retailer's expected profits will increase; when entrusting a third party builds internet channel, the parameters depend on the threshold of supplier's profit sharing ratio. Above all, a numerical example which will indicate the further specific application direction in practice is conducted.

Key words: traditional retailing channel, internet channel, stackelberg dynamic game, products quality control strategy