A seventeen-year-old male presented with a restriction in the oral cavity. The oral mucosa was white and he could not protrude his tongue. For 4 years he had habitually held a powdery material containing betel nut in the oral vestibule for several minutes a day. A biopsy of the labial mucosa was carried out and a diagnosis of oral submucous fibrosis was confirmed. This is a premalignant condition. Oral submucous fibrosis is very rare in young patients.