In this work, we aim to study any relationship between vitamin D deficiency and the prevalence of depression in the population of Mauritius aged between 18 and 40 years. The objectives are to identify the prevalence of depression in vitamin D deficient individuals, and to identify the impact of the level of vitamin D deficiency on the severity of depression. A survey was carried out on 25 individuals who were tested as vitamin D deficient by means of questionnaires. Statistical analysis was performed using SPSS, version 24. The resulting data showed that nineteen, 19 of the participants were suffering from depression and a strong relationship between severity of vitamin D deficiency and the severity of depression was noted (Pearson correlation coefficient, r -0.908 ).The study therefore calls for reinforcing efforts in terms of screening for depression as well as for vitamin D deficiency.