Background: Mental health challenges among university students are pervasive, with alexithymia posing a particularly significant yet understudied challenge. This condition significantly affects an individual’s ability to cope with stress due to difficulties in recognizing, describing, and processing emotions. Objectives: This study aims to evaluate alexithymia prevalence and its associated factors among dental undergraduate students and interns enrolled at King Saud University in Riyadh, Saudi Arabia. Methods: Data were collected through a self-administered online survey that assessed alexithymia symptoms (using the Toronto Alexithymia Scale [TAS-20]), sociodemographic profiles, lifestyle-related factors, and health-related factors. The associations between participant factors and alexithymia were assessed using chi-square and multiple logistic regression analyses. Results: Of the 421 eligible participants, 369 completed the survey (87.6% response rate), revealing a significant prevalence of alexithymia (37.9%). Female gender (AOR = 1.7, p = 0.04), depression (AOR = 5.6, p < 0.0001), chronic diseases (AOR = 3.5, p = 0.003), and childhood abuse (AOR = 2.2, p = 0.047) were independent factors significantly associated with alexithymia. Conclusions: These findings highlight the pressing need for mental health support within dental education. Early interventions targeting alexithymia could mitigate its adverse consequences, promoting better student well-being and academic success.