Neurilemomas are encapsulated nerve-sheath tumors consisting of two histological components; the Antoni A and Antoni B. Their incidence is relatively rare and they can be located in the all parts of the body, but we studied the cases affecting the peripheral nerves. They are usually discovered incidentally as painless masses. In the surgical treatment of neurilemoma which was recommended by Stout et al they must be enucleated with preservation of their parent nerve. Nineteen cases(18 patients) of neurilemoma were treated at the Department of Orthopedic Surgery, Kyungpook National University Hospital, between June 1982 and June 1989. The results were as follows. 1. Of 18 patients, sex ratio was equal. 2. Eleven cases (58%) were between fourth and sixth decade, and the mean age of surgical intervention was 44 years of age. 3. In their anatomical distribution, 14 cases (74%) were on the upper extremity, and 15 cases (79%) were on the flexor surface of body, and the most commonly affected nerve was median. 4. By electron microscopy, the type A cells of neurilemoma had the lamellar pattern of thin elongated cell processes covered by a basal lamina and aggregates of intracytoplasmic microfibrils, and the type B cells were, likewise, covered by a basal lamina, but contained large numbers of organelles and vacuoles. 5. Their first presenting symptom was painless soft tissue mass in 18 cases(95%) and only one case had causalsic type of pain. 6. Among 9 cases of electromyographic study, 7 cases (77%) had no abnormal finding. 7. 18 cases (95%) were solitary, and only 1 case was multiple along a single nerve. 8. On the operative field, 18 cases (95%) were eccentric to the parent nerve. 9. In the size of the tumors, 13 cases (69%) were below 5cm in diameter. 10. In all cases, the authors could enucleate the tumor from parent nerve without injury to nerve. 11. As to the follow-up results, there were no cases of recurrence and malignant change.