The term “mobbing” (moral harassment) in the workplace is defined as the systematic and persistent intimidation, the insult, the exclusion, and the unfair behavior toward a target person. There is little experience regarding mobbing in Greek hospitals, especially among medical residents. In this study, 92 medical residents from the University General Hospital of Patras, Greece (UGHP) were challenged to complete the Einarsen Negative Acts Questionnaire revised (NAQ-R) along with their demographic characteristics. Sector specialty of participants: Internal Medicine, Surgical, and Laboratory Sector. No statistically significant difference occurred relative to sex (p = 0.14), training (p = 0.735), the specialty years (p = 0.478), or years of work as a trainee in UGHP (p = 0.052). Statistically significant difference (p = 0.0174) occured with respect to: (a) age, where at age group 25–35 with regard to to age groups 35–35 and 45–55, and (b) Sector (p = 0.0043) with higher score in the Sector of Surgery, and lowest in the Laboratory Sector (mean = 45.4). Not much data are available regarding the mobbing phenomenon among medical residents worldwide. A review of the literature is also attempted in this study. This research is a pioneer in the Greek medical sector.