本研究探討中國審計市場的脫鉤改制與強制性合夥會計師輪調制度對其審計品質的影響。具體而言，本論文以會計師的簽證意見做為審計品質的代理變數，分析前述中國審計市場的制度變遷與審計品質的關聯性。就脫鉤改制言，實證結果顯示，脫鉤改制提升整體的審計品質；然而，由於法令與管制僅能提升整體審計服務的最低品質水準，故脫鉤改制的效益僅及於中國的小型會計師事務所。就輪調的分析而言，中國的強制輪換制度並未達到提升審計品質之管制目的，並且發現相較於強制輪換合夥會計師，更換會計師事務所的審計品質較差。

本研究以中國大陸2013年至2015年的A股上市公司為研究對象，探討總、分所審計對審計品質之影響。審計品質則以審計意見與可操縱應計盈餘衡量。研究結果發現，本土八大會計師事務所總所比分所出具非標準無保留意見的概率更高，被審計公司的可操縱應計盈餘更小。本研究藉此結果推論，本土八大會計師會計師事務所總所比分所提供更好的審計品質。另外本研究也用Heckman 模型和PSM 模型來克服回歸式的自選擇問題。另外研究進行了的敏感性測試和增額測試，實證結果是穩健的。 / The objective of this thesis is to examine the association between headquarter office auditors and audit quality. This paper uses audit opinion and discretionary accruals to proxy for audit quality. Using a sample of firm-year observations in China during 2013-2015, I find that headquarter office auditors of local “Big 8” is positively associated with higher audit quality. More specifically, the empirical results indicate that firms audited by headquarter office auditors of local “Big 8” experience lower discretionary accruals and are more likely to issue modified audit opinion than branch offices of local “Big 8”. The results are robust after controlling for self-selection bias issue, alternative measures of headquarter office auditors and alternative proxies for audit quality. In sum, this paper provide strong evidence on the notion that head office of local Big8 audit firms have better audit quality than branch office.