Abstract: Under the background of energy saving and emission reduction of the coal industry, this paper studies the joint emission reduction and coordination problems of a two-level supply chain consisting of equipment supplier and coal mining enterprise under government environment regulation.The contracts with or without emission reduction cost sharing are designed under a differential game model, the optimal equilibrium strategies of supply chain members are obtained and compared.It was found that the cost sharing of emission reduction among members of the supply chain can significantly increase their respective profits and emission reduction levels.The environmental preference of customers had a positive impact on the optimal emission reduction and the profits of the members of the supply chain, and the impact was more significant in the case of cost sharing.The sensitivity of optimal emission reduction with cost sharing to government regulation was also significantly higher than that without cost sharing.The higher the sensitivity of government regulation, the more willing coal mine to share the cost of emission reduction of the equipment supplier.