Much of the previous literature has focused on reviewing social capital to discuss its impact, even the profit or loss, but social capital research still has a gap, that is, the possible different mechanisms of its influence process. In view of this gap, this study differs from previous studies by further discussing the various possibilities that may affect the relationship between the social capital and job performance of sales agents. This study discusses whether the relationship between social capital and job performance is affected by corporate social responsibility (CSR), workplace friendship, and proactive personality. Therefore, the purposive sampling method is adopted, where the research object is the full-time sales agents in Taiwan’s finance and insurance brokerage industry.The results of this study showed a positive relationship exists between four conditions: social capital and job performance, corporate social responsibility strengthening social capital and job performance, workplace friendship strengthening social capital and job performance, and proactive personality strengthening social capital and job performance.