Abstract: Based on the introduction of basic model of rational expectation and its policy effects, the essay explores deeply into the policy effects from the view point of the basic model structure and basic assumption of the rational expectation. The results show that “lapsed economic policy ” in rational expectation theory is unaccepted. Taking into consideration of disequilibrium status of pragmatic economic operation, the author finally sets up a nonwalrasian equilibrium model of ancillary expectation variable, and reaches the conclusion that whether economic policies are efficient or not depend on the status of economy.