Objective: We aimed to evaluate depression, anxiety and stress in university students of a large university in Tehran. Iranians witnessed an extraordinary combination of natural and man-made disasters last year; the last of which was the outbreak of COVID-19. Participants: 234 students from Iran University of Medical Sciences. Methods: We designed an online survey to gather data related to General Health Questionnaire (GHQ)-28, Depression, Anxiety, and Stress Scale (DASS)-21, and demographic data. Results: The mean score of GHQ-28 was 34.4 (SD = 15.5, n = 195), and 73.8% (n = 144) of the sample had a score of higher than cut-point (23). According to DASS-21, varying degrees of depression, anxiety, and stress existed in 51%, 32%, and 56% of the students. Conclusions: Negative effects of stressful life events on mental health seems to be additive. More often than not, students need some kind of mental health care at the time of COVID-19 outbreak.