Linear IgA disease (LAD) is an acquired subepidermal bullous disorder, characterized by linear deposition of IgA along the basement membrane. Although the oral cavity is involved in up to 50% of cases, its exclusive involvement is very rare. The case of a 57-year-old woman with 13 months history of desquamative gingivitis chiefly located in the maxilla gingiva is presented. She had been diagnosed by her dental practitioner with an oral infection one year previously and had been receiving local anti-inflammatory and antibiotic medication, with no improvement. She was referred to our Oral Pathology Department, where the biopsy performed revealed a submucosal blister with chronic infiltrate. Direct immunofluorescence showed a linear deposition of IgA in the basal membrane zone, and a diagnosis of LAD was rendered. The patient was treated with topical cortisone, triamcinolone and systemic oral methylprednisolone at a daily dose of 32 mg, and continued at decreasing doses for 3 months. At the most recent check-up, 7 months after initial presentation, she was no longer taking any medication and remained asymptomatic and disease-free.