How to improve the quantity and quality of ESG disclosure is the primary goal of improving the ESG disclosure system. Based on the logic that mandatory ESG disclosure can make up for the insufficiency of voluntary regulation, existing studies mainly argue that mandatory ESG disclosure should be strengthened; however, they ignore the value of voluntary disclosure and the insufficient arguments on why and how to strengthen mandatory disclosure. First of all, theoretical studies have found that voluntary disclosure has the irreplaceable advantage of mandatory disclosure, and its flexibility is more suitable for the personalized characteristics of ESG disclosure and the formation of more effective market information; on the other hand, voluntary and mandatory disclosure are inseparable, and they are related and complementary in terms of system function, disclosure content and system construction.Secondly, the functional positioning of ESG directly affects the choice of regulatory model. If regulators position ESG as a tool to promote long-term corporate value, it belongs to the category of corporate autonomy and adopts a voluntary stance; if they position ESG as a means of social governance, they tend to enhance the mandatory nature of ESG letter approvals in order to achieve the goal of social governance. Accordingly, at this stage of China's dual-carbon governance based on the goal of enhancing the mandatory environmental information disclosure, retaining the voluntary nature of the remaining information disclosure has theoretical and practical legitimacy. Again, although the positioning of the dual regulatory model is reasonable, there is still an endogenous conflict between insufficient regulation of mandatory environmental disclosure and insufficient incentives for voluntary ESG disclosure in the construction of the specific system. The current mandatory environmental disclosure still adopts a single materiality principle, which may result in insufficient supply of ESG disclosure as well as difficulty in coping with the phenomenon of greenwash; there is also the problem of varying standards in the matter of statutory environmental information disclosure. Voluntary disclosure, on the other hand, suffers from a lack of incentives. Listed companies may bear regulatory risks due to ESG disclosure, but there are no rules and exemptions to guide how to avoid them. Finally, in terms of institutional optimization, there are two paths for regulatory enhancement:the introduction of the double materiality principle and the addition of mandatory disclosure. However, considering the fundamental conflict between the social public interest represented by the principle of double materiality and the investor protection interest of the securities law, it is more appropriate to unify the legal environmental information disclosure standard at this stage. On the other hand, the securities law can add environment-related corporate governance structure disclosure matters to differentiate from environmental law information disclosure. There are two paths to incentive enhancement:introducing a safe harbor for predictive information and refining the guidelines. However, considering that there is no domestic rule on predictive information safe harbor and the legislative cost is too high, it is more appropriate to refine the voluntary ESG disclosure at this stage.