This paper studies the recycling channel choice and pricing decision problems for a closed-loop supply chain with corporate social responsibility(CSR). The effect of a dominant manufacturer's CSR behavior to the pricing of new products and the recycling of waste products is analyzed under three different recycling channel structures. It shows that no matter under what recycling channel structures, the CSR behavior of the manufacturer is conducive to expanding the market demand for new products, and improving the return rate for waste products.The CSR behavior of the manufacturer will lead to decrease in its net profit, but it helps to increase the profits of other enterprises and the whole system, as well as maximizing the social welfare. The profit of the manufacturer is always the biggest compared with that of retailer and third-party collectors when the manufacturer undertakes less CSR, however, the retailer's profit will exceed that of the manufacturer on the contrary. From the point of view of expanding the market demand of new products and improving the recovery rate of waste products, it is best for the manufacturer to implement CSR when the retailers are responsible for recycling.