Abstract: One of the options for Chinese enterprise reform is to carry out mixed ownership reform, so the integration of the different natures of capital also leads to the confrontation between the interests of different shareholders. Based on the realization of shareholders′ wealth (index), the paper selects 2006-2015 data of A shares Listed Companies in China as samples to summarize the corporate governance environment present situation from the aspect of the year, and explores the relevance between corporate governance quality and equity capital cost under mixed ownership. The conclusions show that the whole of Chinese corporate governance quality has improved well, and nearly half of the company has achieved the goal of maximizing the wealth of shareholders, but there was still a large space for development; corporate governance quality is inversely proportional with equity capital cost, and the first big shareholder′s nature affects their correlation, and compared with the state-owned companies, the governance quality of the non-state enterprises corporate has more significant impact on the equity capital cost. These conclusions show that the reform of the mixed ownership enterprises is in line with the purpose of market reform, and it can play the non-state-owned shareholders as the controlling shareholder′s governance function. Through the reasonable adjustment of the ownership structure, the equity capital cost of Chinese listed companies can achieve the minimum.

Key words: equity capital cost, corporate governance quality, shareholder wealth, shareholder′s heterogeneity