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The purpose of this study was to investigate the relationship among servant leadership, team effectiveness, and team performance of the Iranian men's volleyball pro-league teams. Descriptive co-relational used as a research design. The statistical sample included players (n=173) and assistant coaches (n=66) from 15 teams. The data collected were gathered using two instruments: (a) The Organizational Leadership Assessment for Sports Teams that adjusted by researcher from The Organizational Leadership Assessment (Laub, 1999), (b) Team Excellence Survey (Larson & LaFasto, 1989). By conducting a confirmatory factor analysis (CFA), all agent factors of two instruments were identified. Pearson, and Spearman correlation, t-test, simple, and multiple regressions were used for data analyzing. The results showed that players' perceptions of servant leadership were moderate and assistant coaches' perceptions of servant leadership were excellent. There was a statistically significant and positive correlation among servant leadership, team effectiveness, and team performance. In addition, servant leadership was a significant predictor for team effectiveness and team performance. The results of this study supported the application of servant leadership in professional sports.