The work aims to optimize and coordinate the interests of participants in the closed-loop supply chain of express packaging recycling and promote the improvement of the recycling rate of packaging wastes. Based on the method of game theory, a closed-loop supply chain model composed of express packaging manufacturers, express companies, Internet recycling platforms and consumers was constructed, the profits in decentralized decision-making and centralized decision-making were calculated and compared, and the revenue sharing contract for coordination was introduced. The results showed that centralized decision-making was significantly better than decentralized decision-making. The profit of participants after coordination was higher than that before coordination, and the range of profit increase depended on the coordination proportion. A numerical example verified the results. The following conclusion is made that the revenue-sharing contract coordination mechanism can improve the profits of the supply chain system, stimulate participants to actively recycle express packaging, reduce environmental pollution, and achieve a win-win situation for enterprises, consumers and society. The government is recommended to actively promote "Internet+" mixed recycling.