中文摘要：

本文以2008～2010年间中国证监会针对会计师事务所的处罚案为对象，以操控性应计的绝对值作为审计质量的替代变量，采用配对的方法，考察行政处罚对审计质量的影响。研究结果发现，在受到处罚后，受罚事务所客户的操控性应计的绝对值会显著下降，且显著低于未受罚事务所的客户，表明行政处罚有助于促使相关事务所提高审计质量，因而是有效的；在处罚前年份，对受罚事务所的客户而言，其操控性应计的绝对值显著高于配对样本，表明受处罚的事务所的审计质量确实较低，因此，证监会的处罚制度是适当的。研究还发现，上市公司所在地区的法治环境并不会影响行政处罚的有效性。

英文摘要：

We use discretionary accruals to surrogate audit quality and investigate the effect of auditor sanctions on audit quality by examining the data of listed clients of accounting firms sanctioned by CSRC in 2008-2010 and their matching companies. The result shows that the sanctioned accounting firms would decrease their clients＇ discretionary accruals （thus increase audit quality） significantly after the sanctions, and, in the years after sanctions, the audit quality of sanctioned firms is significantly higher than unsanctioned firms. Such result demonstrates the effectiveness of sanction system of CSRC. In addition, in the years before sanctions, the audit quality of sanctioned accounting firms is significantly lower than their unsanctioned counterparts. The evidence to some extent supports the appropriateness of the sanction system of CSRC. But the legal environment of clients has little effect on the effectiveness of auditor sanction system.