This paper examines the role of core self-evaluations (CSEs) in the relationships among emotional demands, emotional dissonance, and depersonalization. Data were collected from a non-random sample of 423 teachers who worked in primary, secondary, and higher education institutions. Results from structural equation modeling analysis showed that CSEs displayed both direct and indirect effects on depersonalization through employees' perceptions and reactions to emotional labor. Specifically, those individuals with more positive CSEs tended to perceive the emotional aspects of their job as less demanding, thus being less likely to experience emotional dissonance and, in turn, depersonalization. This research demonstrated that CSEs play a vital role in explaining employees' reactions to emotional labor and, therefore, their effects should be properly accounted for in future studies. Implications for practice and future lines of research are discussed in this paper.