|Background: Many studies reported the outcome of rituximab use in pemphigus, but studies on clinical risk factors affecting clinical outcome or relapse are insufficient. Objectives: The purpose of this study was to find out the clinical outcome and risk factor of relapse in patients diagnosed with pemphigus and treated with rituximab. Methods: A retrospective chart analysis was performed on pemphigus patients who were treated with rituximab in the dermatology clinic of Seoul National University Hospital. Results: A total of 40 patients with pemphigus were treated with rituximab, of which 39 had remission. Twenty-seven patients were treated with less than 2 infusions, while 13 patients were treated with more than 3 infusions. Among them, 24 patients showed complete remission, 15 patients showed partial remission, and 1 patient died during treatment. The most important clinical factor affecting remission and recurrence was the presence of mucosal lesions. The risk of relapse was 4.2 times higher in patients with mucosal lesions than in those without (p= 0.039). There was no statistically significant difference in sex, age, type of pemphigus, number of rituximab infusion (less than 2 or more than 3 infusions), disease duration, and severity score. Conclusion: In pemphigus patients treated with rituximab, presence of mucosal lesions resulted in poor clinical outcome and frequent recurrence. Therefore, pemphigus patients with mucosal lesions should consider more aggressive treatment.