Today, social capital has attracted the attention of many political, cultural, social, and economic intellectuals since its promotion leads to the elevation of various developmental indicators in societies. Like other social doctrines, as should be pointed, the promotion of social capital, too, requires proper infrastructure and conditions where interactions and communications are made among individuals. In other words, since social capital is mainly based on communications, it will become meaningless once communications are lacking among people. That’s the reason, social networks, these days, as an all-encompassing medium, play a key role in providing an appropriate condition for developing effective interpersonal communications. The current study, as such, intends to address the main question: How can social networks promote social capital? To respond to this, first, different aspects of social capital and social networks are examined in order to provide a model. The study employs an integrated method and using a theme analysis of data obtained from various interviews with experts, the most important aspects of social capital and social networks are identified, and finally, using structural modeling and the MICMAC analysis, a model is presented. Based on the results, it is concluded that through conversations as well as news and information obtained on social networks, the greatest impact can be made on social trust and social norms to promote social capital.