中文摘要：

以2009年中国证券审计市场上会计师事务所合并案为例,选取与事务所合并相关的2007—2012年上市公司数据,对事务所合并、签字CPA任期与审计质量的关系进行实证研究,结果显示：会计师事务所合并后审计质量得到了显著提高,合并后未变更事务所的上市公司的签字CPA任期与审计质量正相关。这一结果表明事务所合并后的规模质量效应明显提升,事务所应充分考虑合并初期新任签字CPA的专业胜任能力和保持签字CPA的较长任期,这样更有利于审计质量的提升。

英文摘要：

Taking the merger of accounting firms in China Securities Audit Market in 2009 as case study,selecting the related data of listed corporations from 2007 to 2012,this paper makes an empirical research on the relationship among merger of accounting firms,signature tenure of CPA and audit quality. The research finds out that after the merging of accounting firms,the audit quality has significantly improved and the merged signature tenure of CPA in listed corporations has been positively related to audit quality. The results show that the size and quality of firms merged are obviously improved. Firms merged should take full account of the professional competency of the new signed CPA in the initial stage of the merger and the longer signature tenure of CPA,which are more conducive to the improving of audit quality.