This article addresses the negotiation process between China and Japan over the management of the fishing areas in the East China Sea and the Yellow Sea for thirty years and seeks to clarify the diplomatic motivation behind the change in the Chinese fishery policy toward Japan. Before the resumption of diplomatic relations between China and Japan, the two countries belonged to hostile camps in East Asia respectively. The Chinese government promoted people to people diplomacy to establish diplomatic ties with Japan, and in this context, cooperation in the field of fisheries was advanced. After the resumption of diplomatic relations, the anti-hegemony strategy and the necessity to maintain a good relationship with Japan profoundly influenced China's fisheries policy toward Japan. In conclusion, when China needs to approach Japan diplomatically, it has adopted a more moderate attitude in fishery issues and taken stringent measures when it is dissatisfied with the Japanese government. Examining the post-war fishery relations between China and Japan will not only help us deepen our understanding of the history of Sino-Japanese relationships, but it may also have important implications for further research in China's neighboring diplomacy.