Workplace fun is believed to be an important workplace factor influencing employees' behaviour. But how it influences employees' knowledge sharing is an area that has not gained researchers' attention. Building upon organizational support theory, this study proposes and empirically investigates this relationship through the mediation of organizational inclusion and moderation of authentic leadership. The study uses time lag approach to elicit responses of IT employees, where all in all 494 useful responses are received and used for analysis purpose. The findings reveal that fun at work influence knowledge sharing behavior both directly and through partial mediation of organizational inclusion. The authentic leadership strengths the relationship between fun and organizational inclusion. This study proposes and empirically investigations the role of fun in improving knowledge sharing. It also covers the role of organizational inclusion and leadership in translating fun into outcomes. The mechanism has largely been unattended in existing literature.