Research on the team diversity-team creativity relationship has been mixed. We present and empirically examine a model of mediated moderation in which team knowledge sharing intervenes in the impact of the interaction of team work value diversity and positive mood on team creativity. Survey participants included 458 employees working in 47 R&D teams from 17 research institutes in China. The interaction of team work value diversity and team positive mood positively affected team creativity and was mediated by team knowledge sharing. Our findings suggest that knowledge sharing and positive mood are necessary to facilitate the positive link between value diversity and creativity; otherwise, diversity can have negative effects on creativity. Thus, value diversity, mood, and knowledge sharing should be considered in the formation, training, and performance evaluation of teams.