The aim of this study was to compare athletes' personality characteristics of neuroticism, extraversion, openness, agreeableness, conscintiousness, sociotropy, and autonomy in individual and team sports. One hundred and thrty-four athletes (92 team, 42 individual, 88 males, 46 females) from the Faculty of Physical Education and Sport Sciences, the University of Tehran, and several sport clubs were included in this study. All participants were asked to complete the NEO Personality Inventory-Revised (NEOPI-R) and the Sociotropy-Autonomy Scale (SAS). Analysis of the data involved statistics including means, standard deviations, t-tests, and pearson's correlation coefficients. The results revealed that individual sport athletes scored significantly higher on conscintiousness and autonomy than did team sport athletes. The team sport athletes scored significantly higher on agreeableness and sociotropy than did the individual sport athletes. No significant difference was found between the two groups on neuroticism, extraversion, and openness. It can be concluded that athletes' personality characteristics are different for individual and team sports.