Abstract: Introduction: The critical roles of vitamin D on regulation of immune system and protection of antimicrobial pathways have been revealed; however the protective role of this vital element in protecting body against fungal infections remains uncertain. The present study aimed to compare plasma level of vitamin D in patients with Tinea versicolor and healthy individuals. Methods: This case-control study was conducted on 40 patients with the diagnosis of Tinea versicolor who referred to clinic of dermatology of Rasoul Akram hospital in Tehran between 2016 and 2017. Also, 40 healthy individuals were included as the control. The plasma level of vitamin D was measured by the ELISA technique in both groups. Results: This study showed different frequency of vitamin D3 deficiency between two groups that this different was significant (P = 0.030). This means that frequency of vitamin D deficiency in Tinea versicolor group was higher than control group distribution but the mean plasma level of vitamin D was 17.77 in the group with Tinea versicolor and 21.93 in control group without a significant difference (p = 0.152). Using the multivariable linear regression model and with the presence of baseline variables, no difference was finally revealed in plasma level of vitamin D between those with Tinea versicolor and the healthy individuals (p = 0.164). Conclusion: Vitamin D deficiency may not have a critical role in pathogenesis of Tinea versicolor.