会计师事务所被界定为履行经济鉴证职能的中介机构。就企业年度会计报表审计而言，注册会计师发表的审计意见，是对会计报表所提供信息的可信性的一种保证。就股份制公司特别是上市公司而言，这种保证之所以需要，是由于信息的不对称。在信息占有上是弱势群体的广大中、小股东? An accounting firm is defined as an intermediary agency that performs the functions of an economic assurance function. For the audit of the annual accounting statements of the enterprise, the audit opinion issued by the certified public accountants is a guarantee for the credibility of the information provided in the financial statements. For joint-stock companies, especially listed companies, this kind of guarantee is needed because of the asymmetry of information. In the possession of information is the majority of vulnerable groups, small shareholders?