利率平价理论是用来研究汇率形成机制的理论，可以预测均衡汇率及解释利率—汇率联动机制。研究表明，利率平价理论的解释力在发达的市场更为显著。由于中国市场化程度低、存在资本管制、汇率不能自由浮动，利率平价理论还不能用来预测人民币均衡汇率。本文通过对比中美利率差和人民币远期汇率定价偏差，并进一步运用协整理论对两者进行实证研究后发现，两者存在长期均衡关系。为研究两者间的短期关系，本文又建立了误差修正模型。本文认为，在利率平价理论框架下，由于市场扭曲，中美利率差最终的表现形式是人民币远期汇率的定价偏差。利率差可以作为人民币汇率偏离均衡汇率的参考指标。

Being used to reveal the secret of exchange rate determination, the Interest Rate Parity theory can predict the equilibrium exchange rate and explain the linkage mechanism between interest rate and exchange rate. Researches have shown that the performance of the Interest Rate Parity theory in developed market is more remarkable. Due to the low degree of marketization, capital controls, managed floating mechanism of exchange rate, Chinese market cannot predict the RMB equilibrium exchange rate using the Interest Rate Parity theory. After comparing and further studying the differential trends of Sino-US interest rate and mispricing forward rate using the Co-integration theory, this article discovers a long-term stable equilibrium relationship between the two variables. By introducing Error Correction Model, this article further explores the short-term fluctuations between them. This paper argues that, under the framework of Interest Rate Parity theory, due to market distortions, the mispricing differential of RMB forward exchange rate is the ultimate manifestation of the Sino-US interest rate differential. The interest rate differential performs as a reference index of deviation from the equilibrium RMB exchange rate.