<p>This article explores the ongoing influence of colonialist legacies in contemporary climate governance, highlighting that although the colonial system has ended, its legal and knowledge discourse still profoundly shape global climate politics. Climate litigation is not only a legal tool but also a means of discourse construction. The Western legal framework strengthens its authority in global climate governance through its dominant position in knowledge production, thereby marginalizing the countries of the Global South. To break this hegemony of Western knowledge's universalization and objectification, the Global South must establish an autonomous knowledge system. The article argues that the BRICS countries, as a typical practice of South-South cooperation, play an important role in challenging Western narratives and providing alternative governance models. The article takes the request for the "Consultation Opinion on the Obligations of States in Climate Change" adopted by the United Nations General Assembly in 2023 and submitted to the International Court of Justice as the research background, emphasizing that this historic case provides a unique opportunity to observe the discourse construction and knowledge system of the BRICS countries. This article intends to answer two questions: (1) What is the core discourse of the BRICS countries in climate governance? (2) How are these discourses constructed? Through analysis, this article emphasizes the core position of the knowledge system in legal and political discourses and points out that only by promoting a turn in epistemology can the power structure in global climate governance be changed.</p>