Longitudinal studies suggest the psychological difficulties precipitated by the COVID-19 pandemic have gradually declined, but our understanding of the factors that predict change in mental health is limited. We evaluated the mental health of Mexican college students during the early stage of the pandemic and 4 months later, as well as predictors of change in students’ mental health. Participants were 648 students (71% women, M
age = 21.46) from a private University in Northern Mexico who completed online surveys from May 2020 to September 2020. Students’ self-reported levels of mental health symptoms (depression, anxiety and post-traumatic stress disorder) significantly decreased from May to September. Poor physical health, more COVID-related worry and higher initial levels of peer social support predicted less change in psychological symptoms. On the other hand, more hours of sleep per night and a pre-existing mental health diagnosis predicted steeper decreases in symptoms. Findings suggest reductions in mental health difficulties that are consistent with theoretical frameworks of resilience among Mexican college students. In addition, results underscore the interplay between physical, psychological and social functioning, and the need for continued monitoring of mental health and intervention efforts that address physical health, sleep and pandemic-related worry in University settings.