This study examines the connection between social media use and mental health among tertiary education students. The study was motivated by growing concerns about psychological well-being in digitally-connected educational environments and the need for evidence-based interventions in Zimbabwean contexts. The researchers used a mixed-methods case study design, and the participants consisted of 85 students from Seke Teachers College. The researchers employed questionnaires, semi-structured interviews, focus group discussions, and observations to generate data. The research revealed that students use social media intensively. Usage averaged 6.45 hours daily with 100% WhatsApp penetration. The data revealed that 67.1% of participants experienced depressive symptoms, 74.1% experienced anxiety, 68.2% suffered from sleep disruption symptoms, and 63.6% experienced elevated stress levels. The data also revealed robust relationships between social media usage patterns and mental health outcomes. The use of social media was strongly connected to psychological distress through multiple interacting mechanisms, including social comparison, fear of missing out (FOMO), sleep disruption, and displacement of health-promoting activities. Conclusions indicated that social media significantly impacts student mental health, with students demonstrating awareness of negative effects yet facing substantial barriers to behavior change due to addictive platform design and structural dependence. Recommendations include implementing comprehensive digital well-being education programs, establishing accessible mental health support services, developing institutional policies that establish digital communication boundaries, creating alternative social infrastructure, establishing peer support networks, and conducting ongoing monitoring research. Further research should investigate culturally specific factors that shape social media–mental health relationships in African contexts.