The 14th Five-Year Plan and the report of the 20th National Congress of the Communist Party of China (CPC) put forward the need to pay attention to the modernization of industrial and supply chains, and strive to improve the resilience and security of supply chains. Based on the data of A-share listed companies in Shanghai and Shenzhen from 2003 to 2022, the impact of executive overconfidence on corporate supplier strategic decision-making were explored from the two perspectives of "for the benefit of company" and " for the benefit of oneself". It is found that enterprises with overconfident executives tend to have more centralized supplier relationships, and the impact of executive overconfidence on supplier relationships is dominated by a "for the benefit of oneself" perspective. And centralized supplier relationships are the inevitable consequence of overconfident executives' earnings management behavior. In addition, it is found that resource constraints can negatively regulate the influence of executive overconfidence on supplier concentration. And financing constraints, economic policy uncertainty, and industry competition can positively regulate the impact of executive overconfidence on supplier concentration. The above research expands the research of influencing factors of supplier relationships and clarify the internal mechanism of high concentration of supplier.