The COVID-19 pandemic significantly influenced mental health among university students globally, including in South Africa. The impact in South Africa is further affected by socioeconomic disparities, perception of crisis, individual personality, trust in government, and happiness levels. However, there is limited research on how these factors collectively influence mental health in the post-pandemic context. This study aims to empirically investigate and explore the role of COVID-19 crisis perception, personality traits, trust, and happiness on the mental health of university students in South Africa. A mixed-method approach anchored in embedded-mixed method design will be used, combining cross-sectional surveys to examine statistical relationships and focus group discussions informed by interpretive phenomenology to explore personal experiences. A multiple-stage sampling method will be used to select university students aged 18 and above. Quantitative data will be collected using validated psychological scales and analyzed using SPSS to conduct correlation, mediation, and moderation analyses. Qualitative data will be collected through focus group discussions and analyzed with Atlas.ti and thematic analysis grounded in an interpretive phenomenological approach to identify recurring patterns. Findings of the study will contribute to the understanding of mental health after the pandemic and inform policy recommendations for mental health interventions among university students. The study will adhere to ethical considerations, including confidentiality, informed consent, and participant debriefing.