On the basis of the hypothesis of equilibriums between supply and demand of three sectors,the authors attempt to construct some econometric models, and estimate the impacts of trade policies,international market prices and macroeconomic variables on the real exchange rates.

The paper examines the impact of trade costs on real exchange rate volatility.

This article sets out from the the RMB exchange rate system s historical evolution,it has indicated some characteristics of present RMB exchange rate system,then it draws the conclusion that present RMB exchange rate system exists some question--the compulsive exchange surrender system exists flaws,the RMB lacks the elasticity,the foreign exchange market is imperfect.

The Stage and Rationality of the Current RMB s Exchange Rate Mechanism;

According to the practice of emerging market countries, the choice of exchange rate regime should take into consideration not only the economic principles such as the independence of monetary policy, trade and investment promotion and monetary replacement, but also non-economic principles such as political system, party system and general election.