The stability of executive partners affects companies' sustainable operation, strategy and performance stability, but there is a lack of research on whether it is affected by cultural factors, such as geographical relations. Using the manually collected data of senior executives' hometown relationship, based on the geo cultural background, institutional environment and social identity theory represented by the hometown, the impact mechanism of the chairman's and CEO's hometown relationship on the cooperative relationship between the two sides was analyzed, and the impact of the hometown relationship on the stability of the two partners with Shanghai and Shenzhen A-share listed companies from 2007 to 2016 was empirically tested . The study found that the hometown relationship between the chairman and CEO can significantly improve the stability of their partners, and the improvement effect is increasing from the same province to the same county. The mechanism test found that the hometown relationship improved the partner stability by reducing the agency cost. Consistent with this, the situational test found that when the agency problems of both parties are more serious, such as the quality of internal control is poor, the hometown relationship plays a more significant role in improving the stability of partners. The corporate governance role behind China's unique geo culture was analyzed, the literature on geo relations and executive change was enriched , and a new empirical basis for market parties was put forward to understand the regulatory role of China's unique geo culture on economic development.