Background and aim: Pemphigus vulgaris is an autoimmune vesiculobullous disorder. Prior to the advent of glucocorticoid therapy, it was often fatal. Now its mortality and morbidity is due to highdose glucocorticoid complications rather than the disease itself. This study was aimed to determine the effect of dapsone as a second adjuvant in the treatment of pemphigus vulgaris.Materials and methods: In this quasi-experimental open prospective study, 22 patients with moderate to severe pemphigus vulgaris were treated with prednisolone, azathioprine and dapsone. They were observed for 12-18 months.Results: Patients consisted of 10 females and 12 males with mean age of 41.71 years. The mean duration to reach to the maintenance dose of prednisolone (7.5 mg daily) was 13 months. No major relapse was observed but minor relapses were seen in 6 patients with mean prednisolone dose of 13.8 mg daily. Hemolysis was detected in only one patient and 4 patients had a little drop in hemoglobin level. We observed no other severe dapsone induced adverse reaction.Conclusion: These findings suggest that dapsone can be used as a second adjuvant for more rapid tapering of steroid dosage without significant flare of the disease.