Abstract: The problem involving how member diversity impacts on team ptformance is under debate. The purpose of this study was to explore the differential impact of general diversity (demographic), expertise diversity (education, work experience), and a mediating variable (Transactive Memory System (TMS)) on team performance. Hypotheses were tested with a sample of 65 high-tech work teams in China. Results of path analysis showed that TMS plays the medium role in expertise diversity and team performance, while general diversity directly impacted on the team performance. TMS was significantly and positively associated with team performance.