The impacts of China’s intensified efforts to engage in regional and global environmental governance is widely noted and debated. With rapidly increasing economic and political influence, China has been gradually changing its attitude and strategy in negotiations over some of the most challenging cross-border environmental crises. In this paper, we examine two cases of multinational environmental negotiations, where China exhibited leadership potential and efforts, namely the climate change regime and Mekong river governance system. Our analysis focuses both on the leadership activities around institutional, moral, and financial contributions to the governance regime, and on the efforts for China to take up exemplary actions at domestic level. We argue that in both cases, China exhibited both determination and commitment to shape the course and outcome of the negotiations, whilst applying two clearly different strategies. In the case of climate change, China is using its entrepreneur power to facilitate the deals and portray itself as the moral leader of the climate change course, while in the Mekong river case, financial and institutional inputs are the major instruments for Chinese to assume the leadership role. Yet in both cases, China exhibited a notable shift from an un-cooperative and coercive veto power to a more constructive player in the multinational environmental negotiations.