Drawing on conservation of resources (COR) theory, this paper explores how two dimensions of grandiose narcissism—admiration and rivalry—differently influence knowledge sharing (a resource investment strategy) and subsequent supervisory performance evaluations. Using data from 514 employees across 110 teams, we find that narcissistic admiration is positively and indirectly related to supervisory evaluations on employee performance via knowledge sharing, while narcissistic rivalry shows the opposite pattern. We further reveal the moderating effect of employees’ previous performance. Specifically, employees high in narcissistic admiration are more likely to share knowledge and have higher supervisory evaluations when they have high previous performance, while the indirect negative effect of narcissistic rivalry is not affected by previous. This research extends our understanding of narcissism by articulating how different dimensions distinctly influence resource investment decisions and subsequent supervisory performance evaluations.
