The objectives of this study were to determine the sources of stress among undergraduate dental students, and to compare the sources of stress among the 5 years of undergraduate study, between gender, and with other studies done elsewhere. A total of 325 students across the 5 academic years (88.8% response rate) of the Faculty of Dentistry, Universiti Kebangsaan Malaysia, completed the modified Dental Environment Stress questionnaire. All respondents reported that they experienced some form of stress. The preclinical students reported that examinations and fear of failure caused the most stress. The main stressor for clinical students was clinical training, particularly factors relating to meeting clinical requirements. Female students perceived more stress generally than male students. However, male students were more stressed when faced with factors related to clinical training.