Aim: Vitamin D affects the secretion of antimicrobial peptides associated with toll-like receptor (TLR), which have antiviral effects. It has been suggested that vitamin D may affect the susceptibility of the host to varicella zoster virus (VZV) and the clinical course of zona zoster. Materials and Methods: In this study, 101 patients who were diagnosed with zona zoster at the dermatology outpatient clinic and had a vitamin D result at the time of diagnosis and a control group of 100 people were included. Results were analyzed statistically. Results: The 25-OH vitamin D levels of the patients ranged from 2.37 to 32.98 µg / L and the mean value was 14.25 ± 7.20 µg / L. In the control group, 25-OH vitamin D levels ranged between 10.3 and 44.25 µg / L, and the mean value was 24.9 ± 6.24 µg / L. 25-OH vitamin D levels in the patient group were significantly lower than the levels in the control group. (p <0.001) Conclusion: This study revealed that 25-OH vitamin D levels were significantly lower in patients with zona zoster compared to the control group. 25-OH vitamin D deficiency may increase the risk of VZV reactivation, and vitamin D supplementation in patients with vitamin D deficiency in zona zoster may help the mild course of the disease.