Hereditary benign intraepithelial dyskeratosis (HBID) is a rare disorder first described in 1960. To date, all but one published case trace their ancestry back to an Indian tribe in North Carolina. Affected patients usually develop asymptomatic ocular and oral lesions. The latter may resemble other dermatologic conditions that affect the oral mucosa, such as white sponge nevus. This report describes a case of a Brazilian patient who showed clinical and histological features of HBID, which appears to be the first reported case in South America. Although genetic analysis could not be carried out, the family history suggests a genetic etiology.