Benign cystic teratoma of the ovary was diagnosed histologically in 118 patients over 6 years at the Sir Mortimer B. Davis-Jewish General Hospital in Montreal. The charts were reviewed with respect to population distribution, symptomatology, diagnostic procedures and treatment. Of the 118 patients, 85.6% were younger than 40 years. Only 3.4% had documented recurrence and 6.8% were pregnant. Roentgenograms of the pelvis revealed calcification in 64.1% of cases. Ultrasonography of the pelvis failed to make the diagnosis in 19.4%. The majority of patients had a Pfannenstiel incision (78.8%) and underwent oophorectomy (55.3%). In half the patients the contralateral ovary was only palpated.