Background: Seborrheic dermatitis is a common chronic relapsing inflammatory skin disease with unknown etiology. Using zinc and selenium supplements have shown some relieving effects on the symptoms of the disease. The present study was conducted to determine the relationship between serum selenium, zinc, and copper levels with seborrheic dermatitis. Methods: A prospective case-control study was performed on 30 patients with seborrheic dermatitis and 30 age and sex-matched healthy volunteers as a control group. Trace elements were measured by atomic absorption spectrophotometer in both groups. Results: The mean serum selenium, zinc, and copper levels were 98.90 ± 27.61 ?g/dL, 91.27 ± 10.84 ?g/dL, and 100.9 ± 20.06 ?g/ dL in case groups, respectively. In the control group, the mean serum selenium, zinc, and copper levels were 91.61 ± 15.74 ?g/dL, 94.03 ± 11.11 ?g/dL, and 96.5 ± 15.82 ?g/dL, respectively. There was no significant difference between the mean serum selenium, zinc, and copper levels in case and control groups (P>0.05). Conclusions: Although no statistically significant relationship was observed in serum selenium, zinc, and copper levels between the cases and controls, the serum selenium level among patients in case group was higher than that in the healthy subjects.