Relationships between Big Five Personality Traits and Psychological Well-Being: A Mediation Analysis of Social Support for University Students

University life is a critical period for personality development and psychological well-being. This study, which investigated the relationships between the Big Five personality traits, social support, and psychological well-being, particularly the mediation role of social support, has yielded significant findings. A total of 848 university students (570 females, 67.2%) were conveniently sampled in Taiwan. The results, which showed that female students scored significantly higher on conscientiousness, neuroticism, and social support than male students, with no gender differences for other traits and psychological well-being, provide valuable insights. The mediation analysis, when controlling for gender, demonstrated that social support only mediates the two personality traits (extraversion and agreeableness). Specifically, under the control of social support, the Big Five traits, except for agreeableness, still directly affect psychological well-being. Further, conscientiousness, neuroticism, and openness can directly affect students’ psychological well-being without being mediated by social support, while extraversion can affect psychological well-being in both direct and indirect pathways. Moreover, agreeableness can affect psychological well-being completely by an indirect pathway through social support. These findings not only contribute to the existing body of knowledge but also underscore the importance of personality traits and social support for higher education students’ mental health and adaptive functioning.