Structural Equation Modeling of the Relationships among Machiavellianism, Psychological Entitlement, Moral Disengagement, and Knowledge Hiding among Students of Fee-Based Special Programs (Distinguished & STEM) at the Faculty of Education, Zagazig University Abstract: This study aimed to examine the structural model of the relationships among Machiavellianism, Psychological Entitlement, Moral Disengagement, and Knowledge Hiding among students enrolled in fee-based special programs (Distinguished and STEM) at the Faculty of Education during the Second semester of the )2024/2025( academic year. The main sample consisted of )731( male and female students from the second, third, and fourth academic years, with a mean age of )20.257( years and a standard deviation of )1.408.( The study adopted a descriptive correlational design. Four research instruments were administered—Machiavellianism, psychological entitlement, moral disengagement, and knowledge hiding—developed by the researchers. The validity and reliability of the instruments were verified, and the reliability coefficients indicated acceptable levels.Using Pearson’s correlation coefficient, the results revealed positive and statistically significant correlations among all variables. Machiavellianism was positively and significantly correlated with moral disengagement, psychological entitlement, and knowledge hiding at the )0.01( significance level. Psychological entitlement was also positively and significantly correlated with both moral disengagement and knowledge hiding, and moral disengagement was positively and significantly correlated with knowledge hiding at the )0.01( significance level. Structural equation modeling indicated a satisfactory fit between the proposed model and the sample data and revealed statistically significant direct and indirect effects among all variables. Machiavellianism had a positive direct effect on psychological entitlement (β = 0.921), moral disengagement (β = 0.430), and knowledge hiding (β = 0.137). Psychological entitlement, in turn, had a direct effect on moral disengagement (β = 0.592) and knowledge hiding (β = 0.294). Moral disengagement had a direct effect on knowledge hiding (β = 0.053). The results also showed that Machiavellianism exerted a statistically significant indirect effect on moral disengagement through psychological entitlement (β = 0.233), and on knowledge hiding through both psychological entitlement and moral disengagement together (β = 0.465). These findings contribute to clarifying the underlying psychological mechanisms behind knowledge hiding among university students. The study concluded with a set of recommendations and suggested directions for future research