Abstract: China's interest rate was determined by the regulatory and market liberalization, the interest rate determined by these two forces have different effects on different banks. Using the two-tier Stochastic Frontier Model proposed in umbhaka & Parmeter (2009), the influence of government regulation and interest rates liberalization on the net interest margin of commercial banks in China was respectively studied. It was showed that: (a) Government regulation and interest rate liberation had significant impacts on the decision making of the net interest margin of commercial banks, in which the influence of government regulation was stronger. (b) There were no big interest margins in Commercial banks, and on average, the net interest margin was 7.88% above its theoretical level. (c) Compared with national banks, local commercial banks gained a higher net surplus and was also more vulnerable to government regulation and interest rates liberalization. Also, it was confirmed in this study that the reform of interest rates liberalization had already taken some effects. Therefore, it’s suggested that: During the implementation of interest rates liberalization, differentiated treatments should be applied to banks of different categories.

摘要： 中国的利率决定受管制和市场化两个力量决定，这两种力量决定的利率对于不同的银行有着不同的影响。利用kumbhaka & Parmeter（2009）提出的双边随机前沿模型，实证分析了政府管制和利率市场化这两种效应对我国商业银行净利差的影响。表明：（1）政府管制和利率市场化对商业银行净利差的决定具有重要影响，其中政府管制的影响力更强。（2）商业银行并不存在“高利差”，平均而言净利差高出合理水平的7.88%。（3）相对于全国性银行而言，地方性商业银行获得较高的净剩余，受政府管制和利率市场化的影响也更为显著。由此建议实施利率市场化过程中，对不同类别的银行应当差别化对待。