This study aims to investigate the impact of leader's dark triad personality traits on employee career growth of Mansoura University employees. A questionnaire was used to collect data from 400 employees in Mansoura University. Partial least squares structural equation modeling (PLS-SEM) analysis using Smart PLS Version 3 was employed to show the causal relationships between study variables. The findings of the current study revealed that leader's dark triad personality traits have a significant negative impact on employee career growth of Mansoura University employees. Moreover, the study findings showed that the dimensions of leader's dark triad personality traits named machiavellianism, narcissism, and psychopathy have a significant negative effect on employee career growth.