Thirty-seven discoid lateral menisci of thirty-six patients were treated by arthroscopic means between January, 1987 and June, 1989. A discoid lateral meniscus was present in 15.3% of all patients who have underwent arthroscopy of the knee in this period. It was present in 25.7% of all meniscal lesions and in 39.4% of all lateral meniscal lesions. The average age was 22.7 years and the average length of follow up was thirteen months. Clinically, click sound was the most frequent symptom comprising 86% except knee pain, which was present in all. On physical examination, joint tenderness was present most frequently in 75%. On arthroscopic findings, twenty-eight discoid menisci had the tear and one had severe degenerative change. A tear was most frequently found in posterior horn and the most frequent pattern of tear was longitudinal including bucket-handle and peripheral type. Partial meniscectomy was performed on twenty-nine knees and subtotal meniscectomy on eight knees. At follow up, twenty-nine knees (78.4%) were rated excellent or good and eight knees (21.6%) were rated as fair. There were no poor results. We suggest that arthroscopic partial resection with preservation of normal meniscal shape as much as possible is more excellent than total meniscectomy for the symptomatic discoid meniscus.