The international legal framework developed by the United Nations for the management and sustainable use of fisheries resources has not prevented the severe depletion of world fish stocks. In order to be effective, international agreements have to be voluntarily implemented by national governments. This process of domestic implementation has been little investigated by regime theory, despite the rich array of frameworks developed by policy studies. Therefore, this article seeks to contribute to regime theory through the use of insights coming from implementation research. In order to do so, the domestic implementation of international fisheries agreements in the People’s Republic of China is investigated. Responsible fisheries are not yet a common practice in China, although the country has adapted its legal framework to international requirements. The execution of new laws has been jeopardised not only by the lack of resources, but mainly by institutional conflicts and unclear policy contents.