Introduction: University students’ perspectives on mental health issues remain scarce despite the growing prevalence of mental illness among this population. Therefore, this study aimed to explore university students’ perceptions and beliefs about mental health and mental illness. Methods: Virtual in-depth interviews were conducted from December 2021 to March 2022. All interviews were audio-recorded, transcribed verbatim and analysed using thematic analysis. Results: Sixteen informants from a Malaysian university were interviewed. Four major themes emerged: (1) understanding of mental health and mental illness; (2) perceived causes of mental illness; (3) attitudes towards mental illness; (4) strategies to maintain good mental health. Most informants related mental health to an individual’s thoughts, emotions and behaviours, while a minority equated ‘mental health’ with ‘mental illness’. The majority of informants cited socio-environmental factors as the primary cause of mental illness. Unexpectedly, informants did not view religious factors as a cause of mental illness, although it was thought to be deeply rooted in the older generation. Nearly all informants expressed positive attitudes and willingness to help people with mental illness. However, some informants decided to cover up their mental health problems to avoid the likelihood of experiencing negative emotions. Most informants believed that living a fulfilling and balanced life, staying optimistic and being religious could help them to maintain good mental health. Conclusion: To mitigate the deterioration of students’ mental health, it is necessary to understand their perceptions and beliefs about mental health and mental illness as these may influence their help-seeking behaviours. The study findings showed that university students have a basic understanding of mental health and mental illness and most of them are supportive in handling people with mental illness.