The urban brand is a significant asset for urban sustainable development and it is a distinctive feature among cities. Urban branding is a phenomenon that cities need to reach the sustainable competitive advantage in the globalization age, especially for the social capital development. The main objective of the current research is to investigate the role of urban branding in Germi county’s social capital development. The research is fundamental-applied in terms of objective and qualitative in terms of data collection and it has been done by means of grounded theory. In the present research, by purposive and snowball sampling method, 21 faculty members from urban management, marketing management, executive management, public administration and cultural management, municipal managers and people with urban management experiences were selected and participated in the in-depth interviews and then the data were analyzed by means of open, axial and selective coding, and 409 initial codes extracted from the interviews’ key points turned into 65 more abstract concepts, and by means of comparing and classifying them, 22 items were determined. Paradigm branding model of the causal conditions, contextual conditions, intervening variables, branding strategies and outcomes (social capital development, investment and tourism attraction and development, rural development and immigration reduction, economic prosperity and entrepreneurship, and increasing competitive power in the market) for that city, are considered as the research results.