摘要：本文研究了涉税年报问询函对企业避税行为的影响及其溢出效应。研究结果发现，收到涉税问询函的企业下一年避税程度显著降低。进一步通过文本分析研究发现，涉税问询函的涉税篇幅越大、词频越高、问题越多，对企业避税的抑制作用越强；涉及不同税种和不同性质税收问题的问询函均有治理效果。机制检验结果发现，小规模事务所审计、分析师跟踪人数少、内部控制有缺陷的企业中涉税问询函对企业避税的影响更加显著，表明问询函监管与其他内外部监督存在替代效应。本文进一步对涉税问询函的溢出效应进行了研究，发现涉税问询函在同行业和同事务所两个层面存在溢出效应。本文还发现涉税问询函相比其他问询函对减少企业避税行为具有额外价值。本文的研究结论为交易所非处罚性税收监管提供了实证证据与理论参考。

Abstract: Based on A-share listed companies from 2014 to 2019 in China, this paper examines the regulatory and spillover effect of tax-related comment letters on corporate tax avoidance. We find that companies receiving a tax-related comment letter significantly decrease their tax avoidance degree in the following year. Further analyses show that inquiry letters with longer tax-related length, higher tax-related words frequency and more tax-related inquiry questions further decrease tax avoid behaviors. Inquiry letters related to various tax categories and tax-related problems all have regulatory effect on tax avoidance, and this effect is more significant if the tax-related enquiry letters ask for auditor reply. Mechanism shows that this regulatory effect is more pronounced in companies that audited by smaller audit firms, with lower analyst coverage and defective internal control, indicating a substitution effect between comment letters oversight and firm internal and external monitoring. Furthermore, we focus on the spillover effect of tax-related comment letters, and find that for tax-regressive firms, tax-related comment letters have significant spillover effect in common audit firms and comparable industries. Besides, we also find that tax-related comment letters have incremental value in decreasing tax avoidance compared with non-tax comment letters. Overall, our study sheds light on the regulatory role of tax-related comment letters on corporate tax avoidance.