Part XI of the UNCLOS lays out the legal framework for deep seabed mining activities in the Area. Several countries have already passed domestic deep seabed mining laws fulfilling their obligations under the Convention and the regulations promulgated by the ISA, established under the Convention. China passed its own deep seabed mining law in 2016. China’s deep seabed mining law aims at securing effective regulation of its sponsored contractors’ deep seabed activities and ensuring the contractors’ compliance with the rules and regulations issued by the ISA. China’s law pays tremendous attention to marine environmental protection during contractors’ deep seabed activities. This paper briefly describes the legal regime for international seabed mining, then illustrates China’s legislative actions, examines the key environmental provisions of China’s deep seabed law and analyzes the balancing of interests of multiple parties behind China’s emphasis on marine environmental protection during the exploration and exploitation of deep seabed minerals.