Abstract: Abstract: based on the domestic accounting firm merges in Chinese securities market from 2006 to 2009, the paper analyzes the market reaction, and the effects of merges on audit quality and audit fee. The paper finds that accounting firm merges have not improved the audit quality. The audit fee charged by big accounting firms rose if the firms become the domestic top ten after merges , but the audit fee by small accounting firms have not changed significantly. The market reaction of merge is significantly positive. It indicates that the strategy of growing bigger and stronger encouraged by regulators has taken effect partly. On the other hand, the accounting firms should take steps to integrate the quality control and risk management, and regulators should supervise the quality of merges to help the accounting firms to achieve synergy effects.

摘要： 摘 要：基于2006-2009年间证券市场上内资会计师事务所之间的合并案例，本文分析了合并对审计质量和审计定价的影响，以及市场对事务所合并的反应，发现：事务所合并没有显著提高审计质量；合并前的大所在合并后如进入内资十大则审计收费才会显著上升。小所在合并后其审计收费都没有显著变化；市场对事务所合并做出了显著正面的反应。这一方面表明行业做大做强战略已经取得一定的成效。另一方面，事务所要加强质量控制和风险管理等方面的整合，提高管理水平。监管部门应重视对事务所合并质量的监管，促进合并后事务所实现实质性融合。