Abstract The current managing concept for enterprises is based on the separation principle of managerial authority and ownership, and for this reason, agency costs will result between the proprietor and the businessman. This article probes whether the agency issue may be mitigated through the company’s managing system. The research outcome of this article indicates that the greater the difference between the control power over shareholders and cash flow, the worse the net worth or the rate of return for the operating assets, and therefore the higher the agency costs. Establishing independent supervisors may increase the company’s performance and reduce the agency costs. A president of a company who is also the general manager will increase the operating expenses of the company, which is unfavorable for the company’s managing performance, and will increase the agency costs. The establishment of independent supervisors does not noticeably suppress the company’s expenses. Differing with the efficient monitoring hypothesis for corporations, this research indicates that companies with a higher share of foreign institutional investors have worse performance, showing that foreign institutional investors seem to have not done their best in terms of supervision.