This research contributes to the empirical literature on university student mental well-being by investigating the prevalence and socio-demographic correlates of severe levels of psychological distress. More than 5000 students at a metropolitan Australian university participated in an anonymous online survey in 2013 that included the short form of the Depression, Anxiety and Stress Scales (DASS-21). Comparisons with published research show that our respondents' DASS results were substantially higher than those observed in studies with general community samples, but comparable to other studies targeting university students. Of the explanatory variables analysed, the student's field of study, the number of hours spent studying per week and the number of hours spent caring for family members were all strongly associated with scores in the severe or extremely severe range for each of the DASS scales. These findings provide guidance for policy development, service delivery and further research in higher education.