Knowledge sharing takes part in supporting the era of society 5.0. This study aims to investigate the role of perceived organizational support (POS), servant leadership, and organizational citizenship behavior (OCB) as the antecedents of knowledge sharing. The data were collected via an online questionnaire from 225 public sector employees in Indonesia. Structural equation modeling results indicate that OCB has a significant positive effect on knowledge sharing while also fully mediated POS and servant leadership's effect on knowledge sharing. However, no significant direct effect was found between POS and servant leadership on knowledge sharing. This paper's findings contribute to the establishment of knowledge sharing's antecedents' concept, especially in the public sector. Furthermore, this paper responds to the call for additional research concerning the consequences of OCB in the public sector.