Success and gaining a competitive advantage in the highly competitive world of the information and communication era depends on having satisfied and committed employees to the organization. Hence, organizations increasingly need members who believe that their organization is a good place to work and that they are adequately supported. Hence, organizations increasingly need members who believe that their organization is a good place to work and that they are adequately supported. This causes the employees to have a proper job performance and strive beyond their official duties. Such behavior is called organizational citizenship behavior or good soldier syndrome. In today''s competitive world, it is more necessary than ever for organizations to differentiate themselves through their intangible assets. The purpose of this research is to investigate the impact of the organization''s support from social capital on the commitment and performance of Bank Mellat employees. In this research, which is a descriptive-survey study, the statistical population investigated in this research is 250 employees of Mellat Bank in Tehran. Sampling of the community was done according to the relevant ratio. 200 employees of Bank Mellat answered standard questionnaires. Finally, the data were analyzed using the structural equation test and PLS software. The results showed that organizational support of social capital has a favorable effect on commitment, job performance and organizational citizenship behavior.