Human and Social capitals are the main keys to encourage quality economic growth. The main role of social capital is to increase business competitiveness in a sustainable manner. The social capital is needed to encourage quality economic growth and sustainable competitiveness. Pondok Pesantren is required to support the sustainability of pesantren. However, most Pondok Pesantrens have not maximised their economic potential due to the classical understanding that only physical capital is needed for economics. One of the Pondok Pesantren that optimize social capital as an economic instrument is Ponpes Sunan Drajat. So, it is interesting to study the role of social capital in the economic development through pesantren business units. This research is qualitative approach. Primary data collected with Information from PPSD. Secondary data include journal and media sosial. The three main data collection techniques used by observation, interviews and documentation. Observations are carried out as by economic efforts in Islamic Boarding School that involve the community that happen directly. The results showed that the role of Pesantren trust in developing business units is by attracting business unit community, and strengthen the network ties. Value elements play a role in fostering trust, and norms in keeping values intact. Trust intangible values have become the norm, able to shape the human resources of business unit to become a credible, trustworthy, responsible, honest and fair person so the business unit can be maximised. This finding strengthens the previous studies that theory of social capital can play a role in developing the economy.