中文摘要：

在国内外资本市场上，选择零杠杆政策的公司均呈现逐年显著增长的趋势。本文以2007～2014年我国沪深两市A股上市公司为研究对象，基于主动选择和被动选择的研究视角，研究了为什么上市公司会选择零杠杆政策。研究发现，从主动选择的视角，无外部融资需求、财务灵活性和投资机会分别是导致上市公司最终选择零杠杆政策的三个重要动机；从被动选择的视角，上市公司确实会由于受到融资约束而被动选择零杠杆政策。

英文摘要：

In recent years, firms choosing zero-leverage policy have largely increased globally. Using a sample of public- listed firms traded in Shanghai and Shenzhen stock markets in China from year 2007 to 2014, this paper investigates why firms choose zero-leverage policy from the perspectives of active and passive choices. The results show that, from the perspective of active choices, firms without external financing needs are more likely to become zero-leverage and that financial flexibility and investment opportunities may be the motives for firms choosing zero-leverage policy as well. Furthermore, the findings suggest that listed firms will indeed passively choose zero-leverage policy due to financial constraints.