After the establishment of the new China and the course of the Cultural Rev-olution, under the general trend of reform and opening up, China’s market economy has developed rapidly, and the company’s credit has become more and more important. Since ancient times, honesty has always been the basic morality of human beings, and integrity has always been respected by literati. Integrity is the spiritual leader of a person, the soul of a company, and integr-ity is also the connotation of a country. And social integrity has high re-quirements for the integrity of individuals and companies and even the coun-try because it is related to the interests of everyone. Social integrity is the cornerstone of the market economy’s continuous development in a good di-rection. It is also the foundation of the company’s sustainable management and development. A good social integrity environment can bring hope to in-dividuals, bring opportunities to enterprises, and bring endless power to the country. Based on the importance of social integrity to the market economy, this paper explores the impact of social integrity on the company’s business development by searching and reviewing the literature on social integrity and the cost of equity capital. By analyzing the impact of social integrity on the company’s business development, this paper puts forward a viewpoint: In other words, the cost of equity capital is affected by social integrity and is ne-gatively correlated. And by designing an empirical solution, the data are compiled to prove this point.