自2005年与2015年的两次汇率制度改革以来，人民币汇率的波动加大，企业面临的外汇风险也在逐渐增大。公司能否通过使用外汇衍生品管控汇率风险提高公司价值是一个值得研究的问题。本文基于2013年至2018年A股市场3219家公司的非平衡面板数据，对这一问题进行了实证研究。结果发现在2015年的汇改前，使用外汇衍生品能给公司价值带来约8%的溢价；而汇改后，使用外汇衍生品反而导致公司价值下降了约3%-5%。我们认为这可能是因为汇率制度改革前后人民币的升贬值方向有关，人民币升值时外汇衍生品能降低拥有外汇多头的公司因汇率变动遭受到损失，人民币贬值时外汇衍生品也降低了公司相应的得益。由于多数公司年报未对公司的外汇衍生品的规模以及使用目的进行披露，我们无法准确分析公司使用外汇衍生品的目的是投机还是对冲。我们认为我国的外汇衍生品市场应该进一步发展完善，金融监管机构应该防范可能出现的过度投机现象，公司也应该规范风险管理流程，建立健全相关信息的披露与报告机制，提高外汇衍生品的使用效率与透明度。

Since the reforms of RMB exchange rate in 2005 and 2015, the RMB exchange rate fluctuates more strongly, and the currency risks faced by enterprises have significantly increased. We want to explore whether it is possible for firms to reduce the currency risks through the use of currency derivatives thereby improving firm value. This article conducts an empirical study on this issue based on unbalanced panel data from 3,219 companies in China from 2013 to 2018. It was found that before the foreign exchange reform in 2015, the use of foreign currency derivatives could bring about a premium of 8% to the company's value; after the exchange reform, the use of foreign exchange derivatives actually reduced the company's value by about 3% -5%. We suppose that this may be due to the appreciation and depreciation of the RMB before and after the exchange rate system reform. When the RMB appreciates, for those who long foreign currency, hedgers’ losses are relatively smaller than the non-hedgers’. However, when the RMB depreciates, the foreign exchange derivatives also reduce the hedger's possible gains. Because most companies' annual reports disclose neither the size nor the purpose of the company's foreign currency derivatives, we cannot accurately distinguish whether the firm's purpose of using foreign exchange derivatives is speculation or hedging. China's foreign currency derivative market is developing. Financial regulators should prevent possible excessive speculation. Also, firms are supposed to standardize risk management processes, establish and improve information disclosure system, and improve the efficiency and transparency of foreign currency derivative use.

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