Aim: The main purpose of this research was to investigate the relationship between alexithymia, stress at work, and post-traumatic stress disorder (PTSD) in impact emergency call center operators working in Poland (province of Greater Poland). The risk of exposure to critical life events was also considered. Methods: Data were collected using self-report questionnaires administered after dispatchers’ shifts. The emergency call center operators (N = 66) completed the Impact of Event Scale—Revised, 20-item Toronto Alexithymia Scale, Workplace Perceived Stress Questionnaire, and a questionnaire measuring the frequency and intensity of potentially traumatic events faced by emergency operators (a questionnaire developed by the authors). Results: Twenty of the most frequent events (e.g., child sexual harassment, rape, etc.) were identified. Results indicated that post-traumatic stress positively correlated with (a) work-related stress and (b) one aspect of alexithymia: difficulty expressing feelings. Additionally, work-related stress was identified as a mediator for the relation between alexithymia and the intensity of post-traumatic stress. Conclusions: The results of this study confirm that emergency operators are a high-risk group for the development of PTSD. The study results suggest that performing the work of an emergency dispatcher is not only demanding but also inherently involves participation in potentially traumatic events (as encountered through emergency calls).