Background and aim: Deficiency of zinc -as a necessary trace element-causes exacerbation of acne and development of acne lesions. Also zinc has been used in acne treatment. In this study serum zinc level was evaluated in severe acne cases. Materials and methods: Severe acne cases as well as sex and age matched controls were selected from dermatology clinics of Imam Reza and Qaem Hospitals during 2003 to 2005. Five ml of blood was sampled from each individual and serum zinc level was measured by atomic absorption spectrophotometric method. The mean of zinc serum level between the two selected groups was compared by t and Mann-Whitney tests. Results: Thirty patients (16 females and 14 males) with mean age of 19.8±2.05 years and 28 cases in control group (13 females and 15 males) with mean age of 20.78±2.46 years were included in this study. The mean serum zinc level in patients and control groups were 99.85±18.07 and 101.57±10.52µg/dl, respectively. There was no significant difference between the serum zinc level of the two groups.Conclusion: In this study, there was no relation between the serum zinc level and severe acne disease. Considering the high prevalence of acne and the rarity of zinc deficiency in the general population, the etiologic role of zinc deficiency in acne needs a study in a very large sample, or evaluation of acne prevalence in zinc deficient patients.