随着我国债券市场的日趋成熟，越来越多的企业通过发行信用债筹集资金，使得信用债成为一种比较重要的融资品种。注册会计师在企业债券发行过程中 对其财务报告进行审计并出具审计报告。企业向投资者公开披露审计报告的内容，向投资者介绍财务状况和经营成果。但因相关的监管部门对其并没有建立统一的类似于IPO一样的发行审核标准和信息披露规定，加上注册会计师协会或者会计师事务所内部也鲜有专门关于债券发行审计方面的标准，导致实际执行时发行人、审计机构等对项目的投入也没有上升到此高度，这也使得公司信用债审计质量不能满足相关方的预期使用目的，审计风险随之增加。可见，明确债券发行监管标准、提高审计质量，降低债券发行的审计风险，已经成为审计理论界以及实务界急需解决的首要问题。

    因此，本文选取X会计师事务所审计五洋建设集团股份有限公司（以下简称“五洋建设公司”）公司债项目为研究对象，对信用债、审计风险和审计质量控制方面的内容进行了阐述和梳理，并以审计质量控制理论为核心，明确了本文的理论基础。同时，对该案例的审计质量进行研究分析，以案例分析法为主要途径，以文献查阅法为辅助途径，从顶层设计和监管层面、事务所内部管理层面分析了X会计师事务所审计五洋建设公司债券中质量控制方面存在的主要问题，对原因进行了分析，最后从国家的制度层面及事务所的执行层面提出相应的对策，为会计师事务所审计信用债业务提高审计质量提供一些可以借鉴的参考。

     As the bond market of China grows increasingly mature, more and more companies raise funds by issuing debentures, which have thus become an important financing instrument. During the issue process of the debentures of a company, certified public accountants audit its financial statements and present an audit report and the company discloses the content of the audit report to its investors publicly to provide the company’s financial status and operating results. However, competent authorities have not established unified issue review standards and information disclosure regulations as in the case of IPOs. The Chinese Institute of Certified Public Accountants or accounting firms have set out few standards for bond issue auditing standards. They generally follow the requirements for IPO auditing while the issuers and audit institutions do not live up to these demanding requirements, which increases the audit risk of debentures. It is evident that clarifying regulatory standards, improving the quality of audit reports, and reducing the audit risk of bond issues have become the priority for auditing theory researchers and practitioners.

    Therefore, the debenture issue project of Wuyang Construction Group Co., Ltd. (“Wuyang”) audited by X accounting firm is taken as the research object, and debentures, audit risk, and audit quality control are discussed and reviewed in this study with the audit quality control theory as the core and the theoretical basis of this paper. Meanwhile, in researching and analyzing the audit quality of the project, the case analysis method is used as the major tool, and a literature review is used as the auxiliary tool to analyze the main problems in quality control of the debenture issue project by X accounting firm and the causes from the top-level design, the supervision level, and the internal management level of the firm. Lastly, targeted measures at the institutional level of China and the executive level of the firm are presented with a view to providing reference for accounting firms to improve the audit quality of debentures.