The purpose of this study is to examine leader-member exchange (LMX) and personal guanxi between its relationships with organizational citizenship behaviors (OCBs) and to test empirically whether this relationship is mediated by corporate social responsibility (CSR) in financial service personnel. Drawing a sample of two hundred and twenty-eight financial service employees, we tested several causal hypotheses pertaining to antecedents and impacts of organizational citizenship behaviors by means of structural equation modeling to measure the relationship among the constructs. The empirical results illuminate that leader-member exchange (LMX) and personal guanxi are significant relationship with organizational citizenship behaviors (OCBs). When CSR is introduced into the model, the previously highly significant relationships between LMX and personal guanxi with OCBs becomes insignificant and much weaker. The mediating effect of CSR can positively influence OCBs of financial service personnel and in turn job performance of employees. Implications of the findings are discussed and directions for future research are suggested.