中文摘要：

具有基金评级资格的证券公司与证券投资基金之间存在着紧密而有趣的经济关系，一方面，具有基金评级资格的证券公司可以对基金进行评级，另一方面，基金与证券公司之间可能存在利益关联，具体体现在：1）基金要通过证券公司的交易席位进行交易并相应地给予证券公司交易佣金；2）证券公司可能是投资基金的大股东．那么这两种利益关联会损害证券公司作为基金评级机构的公正性吗？研究发现：1）如果证券公司与投资基金之间存在交易佣金关系或股权关系，那么证券公司会显著提高基金的评级等级；2）通过利益关联获得的基金评级对基金未来业绩解释力明显较低；3）2010年实施基金评价资格管制之后，上述两种现象更为明显．综合研究结果表明，利益关联会损害证券公司作为基金评级机构的公正性，且基金评级资格管制可能进一步加剧了利益关联对评级公正性的损害．

英文摘要：

There are closely and interestingly economic ties between funds and the security firms with qualifi- cations of rating funds. On one hand, these security firms provide ratings for funds. On the other hand, funds may be economically connected with these security firms through the following two ways. First, funds pay trading commission fees to security firms since they need trading seats from security firms. Second, these secu- rity firms may be large shareholders of mutual funds. Then, will these two kinds of connected interests harm the independence of these security firms when rating funds ？ This paper finds that ： i ） if there are trading com- mission fees or ownership relationship between funds and rating security firms, security firms offer higher rating for funds ; 2） the rating under the shadow of connected interests has lower explanatory power for future fund performance ; and 3 ） the above two effects are more significant after 2010 in which year the regulation system of fund rating qualification was enacted. Those findings show that connected interests damage the independ- ence of security firms as fund rating agencies, and the regulation system of fund rating qualification further exacerbates the damage.