Background: Prolactin, a neurohormone, can act as a stimulator of immunity in a number of autoimmune diseases and its high levels have been shown in these diseases. Objective: This study was designed to discover the possible role of prolactin in autoimmune blistering skin diseases. The main goal was to compare the serum prolactin levels and the frequency of hyperprolactinemia in autoimmune skin patients with a control group. Patients and Methods: Serum prolactin levels were measured in 44 patients with autoimmune blistering skin diseases and 44 age and sex matched normal persons. Results: The mean serum prolactin level was higher in the patients group than the control group (13.7 ng/ml vs. 8.4 ng/ml). Seven of 44 patients (16%) had hyperprolactinemia, which was significantly higher than control group (P=0.006). Conclusion: According to this study a higher frequency of hyperprolactinemia was observed in patients suffering from autoimmune blistering diseases in comparison with a control group.