In contexts where poverty and mental health stressors already interact to negatively impact the most vulnerable populations, COVID-19 is likely to have worsened these impacts. Before the COVID-19 pandemic, adolescent girls and young women (AGYW) in South Africa already faced intersecting mental health stressors and vulnerabilities. It is critical to understand how additional challenges brought on by COVID-19 have intersected with existing vulnerabilities and mental health risks AGYW faced, particularly given the intersections between psychological distress and increased risk behaviours that impact sexual and reproductive health. The authors aimed to examine socio-economic and mental health impacts of COVID-19 on South African AGYW in order to understand how additional challenges brought on by COVID-19 have intersected with existing challenges, compounding AGYW vulnerabilities.