Parry-Romberg syndrome is an uncommon degenerative disorder characterized by a slow and progressive atrophy of the subcutaneous tissue on one side of the face. Its etiology is unknown, and there is no cure. It is usually seen in children. Surgical reconstruction is often the best treatment option, and a wide variety of techniques have been employed. It is often difficult to diagnose Parry-Romberg syndrome because its signs and symptoms overlap with those of several other disorders. We describe a case of Parry-Romberg syndrome in a 42-year-old woman, whose age at onset was the unusual feature of this case.