The recent polycrisis (COVID-19, Ukraine war, climate change, economic crisis) has been associated with mental health through cumulative stress, with young people being particularly vulnerable. We surveyed 403 college students from Poland to examine their psychological responses to the experienced crises. The results showed that polycrisis was associated with worse mental health of college students from disadvantaged groups (based on gender, sexual orientation, and financial situation) compared to other college students, in four areas: sense of proximity to the crises, stress caused by the crises, sense of responsibility for mitigating the crises, and experiencing everyday moral dilemmas regarding the crises. These young adults also suffered more in terms of negative affectivity, depressive symptoms, and subjective physical and mental health. Our findings suggest that when discussing public mental health perspectives, it is important to consider consequences of cumulative stress and its greater impact on young people from disadvantaged groups.