<p><strong>Background:</strong> Colour vision defects are expected to have a negative impact on daily activities, education, misguided career choices, and mental and social well-being. Its prevalence among university students in South Africa remains unknown.</p><p><strong>Aim:</strong> This study aimed to investigate the prevalence of colour vision deficiency (CVD) among male university students and its adverse effects on education, emotions, social life and everyday tasks.</p><p><strong>Setting:</strong> The study was conducted in all colleges of the selected university.</p><p><strong>Methods:</strong> Purposive sampling was used to select 272 male students aged 18–30 years, at all colleges of University of KwaZulu-Natal (UKZN). The Hardy-Rand-Rittler colour vision test (HRRT) and Ishihara colour vision test were used for the assessment of colour vision. The CVD-AES questionnaire was used to assess the adverse effects on participants with CVD in four subscale areas, viz. education, social life, emotion, and everyday tasks.</p><p><strong>Results:</strong> A total of 272 male students, with a mean age of 20.61 years (s.d. = 2.08), participated. The occurrence of CVD was noted in 19 (7%) participants, with the majority (74%) being unaware of this defect. The most common type of defect was deutan (6.5%). Participants’ responses indicated adverse effects on education, emotions, social life and everyday tasks, with CVD having a greater impact on the latter two.</p><p><strong>Conclusion:</strong> The occurrence of CVD among male university students is significant, with many of them being unaware of it. Social life is most adversely affected, but adverse effects are noted in all subscales.</p><p><strong>Contribution:</strong> This study provides further evidence to the prevalence of colour vision deficiency and its impact on quality of life.</p>