中文摘要：

建立股票市场的初哀是为国有企业改革创造条件，解决国有企业所有者缺位引起的内部人控制问题。那么，这一初衷是否实现了呢？文章以民营企业为参照，首次实证检验了上市对国有企业经营者代理问题的治理效果。研究发现，上市对国有企业股权代理成本的影响是条件依存的，上市显著降低了非竞争性环境中国有企业的代理成本，而对竞争性环境中国有企业代理成本的影响则不显著。这表明作为一种特殊的外部治理机制，上市与市场竞争对国有企业代理问题的治理效应存在替代关系。

英文摘要：

The original intention of the establishment of stock market is to provide conditions for the reform of state-owned enterprises, and especial- ly solve the problem of insider controlling resulted from the owner absence in SOEs. However, does this intention come to true？ This paper sets private enterprises as a benchmark, and empirically studies the governance effects of listing on the agency problem of managers in SOEs for the first time. It shows that the effect of listing on the equity agency costs of SOEs depends on conditions. Listing significantly decreases the agency costs of SOEs in weakly competitive markets, but has no influences on agency costs of SOEs in intensively competitive markets, showing that as a special external gov- ernance mechanism, listing is a substitute for market competition with re- gard to the solution to the agency problem in SOEs.