The global marine environment is threatened by acidification but lacks adequate governance, and current international legal regulation is in a “regime complex” dilemma. Continued fragmentation of the oceans and environment regime will impede the development of joint systemic governance of ocean acidification, and an integrated approach to regulation is necessary. One possible solution is to provide a specific legal framework for a comprehensive response to ocean acidification through the United Nations Convention on the Law of the Sea (UNCLOS), which is open, inclusive and keeps pace with the times, to lead regulation, with other multilateral environmental agreements (MEAs) providing specific rules and standards to guide the international community to act in a unified manner. Whether such a solution can achieve its regulatory goals depends on whether other MEAs are applicable to UNCLOS parties and whether they provide targeted regulatory measures for ocean acidification. However, the general lack of attention and sensitivity to ocean acidification in the existing major MEAs is an obstacle to the development of effective regulatory measures. Currently, starting from three dimensions including slowing down and reversing the trend of ocean acidification as much as possible, proactively intervening in ocean acidification that has emerged and enhancing the resilience of marine ecosystems, countries can seek opportunities for consensus and collective action to address ocean acidification in the context of the development process of major MEAs, promote the development of the relevant international legal regime as soon as possible, including the addition of relevant provisions or enrichment of treaty interpretation based on existing treaties, and introduce practical measures to effectively regulate ocean acidification. In addition, consideration needs to be given to set explicit CO2-reduction targets that are directly linked to ocean pH in climate agreements.