Among the various efforts coping with the causes and roots of differences in economic development in Iran and South Korea, none has focused on the role of Social Capital. Meanwhile, in recent years, we have been facing the development of a theory about the linkage of social capital and economic development and a great attention has been paid to it by International economic organizations. In this article we have evaluated the theory in an empirical study in Iran and South Korea. According to the results, there is a significant relation between low levels of social capital in Iran and failure in achieving development objectives. On the other hand, high levels of social capital in South Korea contribute to the country's privileged position in terms of economic development.