Background: acne vulgaris is a chronic inflammatory disease of the skin that affects the individuals of all ages, especially adolescents. An association between serum zinc levels and acne vulgaris have been reported in some studies. Objective: the aim of our study was to estimate serum zinc level in patients with acne vulgaris and healthy subjects and its association with severity of disease. Patients and Methods: this study was conducted on 60 patients (subdivided into 4 groups according to severity of disease according to Global Acne Grading System) and 60 normal individuals as a control group. Results: there was highly significantly statistical difference between all patients and control groups as regard serum zinc level (mean of serum zinc level in patients and control groups were 49.85 ±19.61 and 63.46 ± 22.95 respectively, p=<0.001). Conclusion: it is concluded that zinc deficiency in acne patients could be one of the causes of acne and also that zinc levels may not be related to the severity.