The Environmental Performance Clause in CPTPP has soft law attributes, yet China has insufficiently paid enough attention to studying it, resulting in a lack of theoretical guidance and practical scenarios in the connecting process. China will face dual dilemmas in the process of connecting: the lack of domestic mechanism and risks of international recognition. In terms of the lack of domestic mechanism, China has not yet established a unified standard for voluntary disclosure of environmental information by enterprises, which makes it difficult to guarantee the quality of environmental information in enterprises’voluntary environmental audits and reports. In terms of international recognition risks, although China’s environmental labeling system and environmental subsidy policies comply with WTO rules, the recognition of China’s environmental labeling system still needs to be further improved. Moreover, while the United States and the European Union adopt specific and discriminatory environmental subsidy policies, they have issued erroneous countervailing duty rulings against China’s environmental subsidies in sectors such as renewable energy and electric vehicles. To effectively connect with this clause, China should internally improve its voluntary environmental information disclosure standards for enterprises; externally, it should promote the international mutual recognition of environmental labeling system and advocate the legitimacy of its environmental subsidy policies.