Neurilemoma usually discovered incidentally, is a benign nerve-sheath tumor which has been described as a painless mass. In most cases, the size of the mass was smaller than 5cm. However, it was reported that there were masses, sometimes associated with local tenderness and pain, whose size was over 6cm. Then, we have found there is a relationship between mass size and neurologic symptoms, as well as with, postoperative complications. It is important to diagnose early and to treat it. Twenty neurilemoma patients, who were treated at Keimyung University Dongsan Medical Center were analyzed using their clinical symptoms, pathologic findings, radiologic findings and complications. There was no sexual difference in tumor incidence. The anatomical locations of tumors were as follows. ; upper extremities in 15 cases(69%), axilla in 1 case(4%) and lower extremities in 6 cases(27%). Symptoms were palpable mass in 22 cases, local tenderness in 8 cases(36%), radiating pain in 6 cases(27%) and paresthesia in 6 cases(27%), Median nerve was involved most frequently(33%). There were 2 patients(10%) with multiple symptoms. Tumor enucleation was done in all cases. The size of tumors in longest axis was smaller than 2cm in 2 cases, between 2 and 4cm in 11 cases and more than 5cm in 9 cases. There was no case of malignant transformation or recurrence. In conclusion, incidence of clinical symptom and postoperative complications are increased with the size of the tumor especially over the 5cm. Preoperative MRI finding was the most accurate method of diagnosis and most helpful in determining surgical resection margin.