本文通过对2001至2004年中国上市公司数据分析后发现,多元化显著增加了上市公司经理人的代理成本。通过追溯上市公司控股股东的终极控股性质显示,民营控制上市公司的多元化水平与经理人代理成本无显著关系;而国有控制上市公司多元化与经理人的代理成本显著正相关。 This paper analyzes the data of Chinese listed companies from 2001 to 2004 and finds that diversity significantly increases the agency costs of listed company managers. By tracing the ultimate controlling nature of the controlling shareholders of listed companies, it shows that there is no significant relationship between the level of diversification of listed private companies and the agency costs of managers, while the diversification of state-controlled listed companies is positively correlated with the agency costs of managers.