Power plays a fundamental role in the system in the international relations. Basie on Game Theory, and by the assumption that the total amount of power is relatively constant in a short period of time, this paper makes a modelling analysis of the "take-and-give" movement of power among rational countries. Based on building the curve of power taken and the curve of power given, the power balance mechanism model and the power movement track model are constructed. We also make an analysis and by the examples. In the current situation, this paper agrees with the view of most scholars. China and the United States have opened a "cold war" different from the United States and the Soviet Union. With the coordination between the PRC-US relations, it is concluded that a stable international power mechanism requires the active cooperation of all countries, which could promote the power operation to reach the equilibrium point. The analysis method of power movement can explain the cause, progress, and trend of Sino US cold war to a certain extent.