中文摘要：

选取2007～2012年沪深A股上市公司的CEO为研究对象，探讨CEO年龄对上市公司市场风险和公司风险决策特征的影响。实证发现：CEO年龄越大，其所在公司的市场风险越小。进一步研究表明：老年CEO主要通过低风险决策行为来减少公司的市场风险，即：老年CEO在研发上投资较少，其公司经营杠杆比率以及过度投资程度相对较低。这一结论对于我们更好地理解老年CEO的风险决策行为，及对不同风险特征的上市公司如何聘请不同年龄的新CEO具有一定的启示意义。

英文摘要：

We study CEO of listed companies in A-share stock market from 2007 to 2012, and try to find out the influence of their age on both the characteristics of market risk and risk-taking behavior of listed companies. Our evidence indicates that smaller stock return volatilities tends to correlates with greater CEO ages. Further study shows that, older CEOs reduce firm risk by less risky investment policies, such as investing less money in Rb-D, maintaining lower operating le- verage ratio and lower degree of over-investment. The conclusion provides a better understanding of older CEO risk-taking behavior, and evidence of hiring CEOs based on age for the different risk characteristics of listed companies.