Abstract From the perspective of switching costs theory, using mathematical analysis and game theory and combining qualitative with quantitative method, the author studies East Asian currency game. The monetary cooperation is a win-win game for East Asian countries|the game between China, Japan and other East Asian countries is a "boxed pig game" and China and Japan will gain more benefits from the monetary cooperation|The game between China and Japan is a similar "chicken game", and the competition around dominant currency is inevitable during the monetary cooperation. China should actively promote East Asian monetary cooperation and the course of RMB internationalization and strive to make RMB the dominant currency in East Asia