A case of hemimandibular hyperplasia in a young patient treated 12 years ago is presented. Clinical and radiographic findings were consistent with a diagnosis of right hemimandibular hyperplasia. An early high condylectomy was performed. In our opinion, the esthetic and functional results after this long-term follow-up are fairly satisfactory. We present a brief review of the literature to make a differentiation between condylar hyperplasia and hemimandibular hyperplasia and to stress the importance of early condylectomy to correct this disease.