Objective: The aim of this report is present a rare case of oral Mucous Membrane Pemphigoid (MMP) in a 9-year-old-boy successfully treated with low doses of systemic corticosteroid. Case description: A 9-year-old boy was referred to our service with the complaint of painful gingiva and generalized burning mouth sensation over 1 year. Intraoral examination revealed desquamative lesions affecting the entire attached gingiva of both the maxilla and the mandible. After the incisional biopsy the MMP diagnosis was confirmed, and the patient was initially treated with dexamethasone 0,1mg/Ml mouth rinse twice daily for 24 weeks. Due the difficulty in eating and the presence of persistent large oral lesions, systemic prednisone 20 mg (1 mg/Kg) was prescribed for 4 weeks with a 5 mg gradual reduction per week over 3 weeks. After initiating the systemic corticosteroid therapy, the patient showed total regression of the lesions, and no indication of recurrence has been observed in the past 6 months. Conclusion: There is no cure for MMP; however, treatment can provide complete and long-lasting remission. Based on this premise, it is plausible to consider not only topical but also low doses of systemic corticosteroids in resistant cases of oral MMP, even in children. These measures could improve the quality of life of these patients by reducing pain and, consequently, improving the child’s eating behavior.