Previous literature show that auditors and the public have different understandings and beliefs about the auditor’s responsibilities.The public’s expectation of statutory audit may exceed the responsibility required by the auditing standard,which leads to the audit expectation gap.Since the 1980s,there are more and more criticisms on statutory auditors especially after the appearance of some auditing fraud such as Enron case in the United States and Maxwell’s case in the United Kingdom.The misunderstanding from the public makes the auditor face more and more challenges.The purpose of this paper is to discuss the components of the gap,and discuss the main reasons based on the existing literature and cases.This paper makes a critical evaluation of the audit expectation gap from three parts:performance gap,standard gap,and reasonableness gap,respectively.