Hidradenitis suppurativa (HS) is a chronic inflammatory disease of the apocrine gland bearing skin, presenting various stages of flexural skin pain, erythema, painful nodules, abscesses, sinuses, and fistulas. We aimed to assess serum vitamin D levels in patients with (HS) in Jordan. a cross-sectional comparative study conducted among 110 patients with HS and 110 matched controls, who didn't previously receive vitamin D therapy. Serum vitamin D was measured and classified into normal (>30 ng/ml), insufficient (20-30 ng/ml), and low (<20 ng/ml). The mean age of the cases was 43.1 ± 12.9 years and the mean disease duration was 19.4 months. The mean body mass index among patients with HS was 30 and about 34% of them were smokers. The mean Vitamin D level was 8.4 ng/ml and all HS patients were vitamin D deficient. Patients of HS were more likely to have vitamin D deficiency compared to healthy controls. Most of the study subjects and particularly all of the patients with HS have low vitamin D levels. Smoking and high BMI, were associated with HS. We suggest the implementation standard public dietary recommendations of Vitamin D supplementation, smoking cessation, and weight reduction behaviors with further assessment of disease course among HS patients.