The purpose of this study is to determine the knowledge and opinions of school principals about the concept of the social capital. This research is deemed essential regarding increasing the awareness of school administrators who could play a significant role in mobilizing the potential social capital in schools. The study has been conducted in a qualitative design in the direction of this purpose, and the data of the research have been obtained by using the semi-structured interview form. The participants of this study consisted of 20 voluntary school principals. The data have been collected and digitized under the common categories after encoding. According to the findings of the study, the school principals indicate networks (social relations), trust and norms as the factors that create the social capital. It is observed that they benefit from the networks (social relations) dimension of the social concept most. Besides, it is seen that the school principals who can reveal the social capital can use the trust and social networks elements more useful. It is thought that the findings of the research would contribute to the better understanding of social capital by school principals and the realization of the social capital in schools.