A mediating model to explain the relationships among employees' knowledge sharing (KS), guanxi, and innovative service behavior (ISB) was developed and tested. Results support guanxi's role as a mediator of the relationships between KS and ISB and serve as a constructive replication of the hypothesized relationships. Supporting prior research, it was found that KS is associated with increased ISB for individuals with a favorable guanxi. Results from empirical studies demonstrate strong support for the effects of KS, guanxi, and ISB. A structural equation analysis reveals that the mediating model has strong predictive ability for KS to ISB.