中文摘要：

宏观经济和资本结构是影响融资成本的重要因素,随着我国经济进入中低速发展阶段,经济体系中不确定性因素增加,企业融资成本增大。文章主要运用动态资本结构理论,研究宏观经济增长以及资本结构波动对企业债务资本成本的影响。通过对2004—2012年沪深股市上市公司财务数据的实证分析,研究发现：资本结构波动能够助推资债务资本成本上升;宏观经济增长有利于债务资本成本降低;在宏观经济发展速度较低的情况下,资本结构波动对债务资本成本的影响更为显著。因此,在当前宏观经济速度放缓的背景下,市场不确定性的增加将带来资本结构波动提高,债务资本成本也将进一步上升。

英文摘要：

Macroeconomy and capital structure are important factors which affect capital cost. As China＇s economy steps into a development stage at a medium and low speed, there is more uncertainty in economic system and more capital cost in the firms. Using dynamic capital structure theory, this paper studies the impact of macroeconomy development and capital structure fluctuation upon firms＇ debt capital cost. After an empirical analysis of the financial data in listed companies on Shanghai and Shenzhen Securities Exchanges, this paper finds that ： capital structure fluctuation gives rise to an increase of debt capital cost ; macroeconomic growth can depress the growth of debt capital cost ; when macroeconomic growth slows down, the capital structure fluctuation has a more significant effect on debt capital cost. Therefore, under macroeconomic slowdown, the debt capital cost increases with the impact of capital structure fluctuation due to more market uncertainty.