中文摘要：

金融危机对公司行为的影响吸引了理论界和实务界的共同关注。由于企业所得税是公司重要的现金支出,而且公司避税在世界范围内普遍存在,因而从公司避税活动视角探究金融危机的影响显得尤为重要,然而已有文献关注此问题的还不多。鉴于此,本文首先检验金融危机对公司避税的影响,并进一步检验融资约束程度、外部金融市场环境等对二者间关系的调节作用。检验结果表明,金融危机期间,伴随外部融资环境恶化,公司的内源融资需求提高,另外风险转移倾向也会变得更为明显,这些都使得公司的避税程度显著提高;与融资不受约束公司相比,融资约束公司金融危机期间避税程度提高更为明显;伴随公司所处地区金融市场化程度的提高,金融危机对公司避税程度的影响被削弱。本文的研究成果不仅丰富了金融危机微观作用机制方面的学术文献,而且还提供了公司避税程度影响因素方面新的经验证据。

英文摘要：

Subprime crisis originated from the United States resulted in great impact and destruction to the global financial markets, which caused the financial markets a strong credit crunch effect. As the most important micro components of the economy, firms would therefore suffer a substantial impact from the financial crisis and their behavior may change as a result. In fact, whether and how financial crisis affects corporate behavior attracts both theorists and practitioners＇ concern. There are lots of studies on the impact of financial crisis on firm＇s behaviors, such as firm＇s research and development expenditures, capital expenditures, employment, and dividend policy, and so on. As corporate income tax is a significant cash outflow and tax avoidance exists widely around the world, thus it seems extremely important to explore the impact of financial crisis on tax avoidance. However, there is still limited evidence on this issue. In view of this, we first examine the impact of financial crisis on corporates＇ tax avoidance to what extent. Further, we examine whether financial constraints and external financial marketi- zation moderate this relationship. The empirical results suggest： （1） During the financial crisis, corporate＇s internal financing need and risk-shifting tendency all increased due to the deterioration of the external financial environment, and thus companies became more tax aggressive. （2） Compared with financial unconstraint compa- nies, financial constraint companies became much more tax aggres- sive, which suggests that individual firm＇s difference in financial constraint had a different impact on the effect of financial crisis. （3） Accompanied with the increase in external financial marketization, the impact of financial crisis on tax avoidance was weakened, which indirectly indicates the positive effect of financial marketization on firms＇ financial constraints. These findings not only enrich the literature on micro mechanism of financial crisis which provide reference v