This research tries to develop a conceptual model to improve company value which is a key indicator in showing agent performance, in this case the manager, but an agency conflict sometimes arises. When investors as company owners sometimes find a condition of bias that will cause agency conflict. A concept of corporate governance exists as a solution to resolve. Together with outside ownership of the company and company performance, a basic model is proposed to solve this problem by using company performance as mediation through corporate governance and the ownership structure 3 hypothesis is proposed. The model was tested on 90 companies listed on the Indonesian stock exchange using AMOS as a data analysis tool and 3 hypotheses were accepted. The role of company performance which plays a role as a mediator has been able to show its role as an antecedent to driving the increase in company value.

Keywords: ownership structure of corporate governance; company performance, company value.