Social capital is one of the most important assets of communities which lead to social cohesion of social capital. It affects the various sectors of society and organizations on different aspects of identity and social behavior. This study uses the theories of thinkers like Coleman, Putnam, Lynn, Bart and Wellman and to investigate the relationship between social capital and forgiveness tendency in Sanandaj city. In order to measure the different dimensions of social capital from one the one hand and on the other hand tendency towards the forgiveness among 500 persons aged 20 years living in Sanandaj, questionaries were completed. The results indicate that women tend to forgiveness more than men. The dimensions of social capital, including social solidarity (0.653), social trust (0.622), political trust (0.212), social relations(0.523), and civic participation (0.70) are associated with a tendency to forgiveness. However, social awareness is not significantly associated with a tendency to forgiveness. Moreover, according to the findings of the study, the relationship-based social capital and the tendency towards the forgiveness is confirmed.