Abstract: 【Abstract】 Objective: To investigate the clinical curative effect of arthroscopic meniscus plasty on discoid meniscus in children. Methods: From January 2003 to April 2009, 31 children ( 33 knees ) with discoid meniscus injury were treated in our hospital, including 18 males and 13 females, with 9 cases in left knee, 20 cases in right knee and 2 cases in both knees.This group of children aged 4 to 14 years old , with an average of 11.3 years old. This group of pediatric patients with preoperative symptoms included: tenderness in joint gap (20 cases), pain on motion (13 cases), positive McMurray sign (25 cases), positive Apley sign (14 cases), joint interlocking ( 11 cases ), claudication ( 31 cases), flexion deformity (23 cases), and quadriceps atrophy (29 cases). The duration between appearance of symptoms and visiting a doctor was from half a month to 3.5 years, with an average of (8.2+1.5) months. The function of knee joint was evaluated according to Lysholm scorcing system. Results: All 31 patients (33 knees) underwent arthroscopic partial meniscectomy plasty or subtotal resection and 33 knees were confirmed as discoid meniscus. According to Watanabe typing system, there were complete type in 27 knees, incomplete type in 4 knees and Wrisberg ligament type in 2 knees. Preoperative symptoms of all patients were obviously improved. The wound of the patient healed well, with no infection. All patients were followed up 12 to 24 months. Preoperative mean Lysholm score was (51.8 + 2.6) points (range, 35-66 points), and the Lysholm mean score was (92.5 + 1.7) points (range, 79-95 points) at 12 month after operation. There were significantly statistical difference between preoperative and postoperative Lysholm score ( P < 0.05 ). Menisci tear and patient needs the second surgery were not found during the follow-up. Conclusion: Meniscus plasty applied in the treatment of discoid meniscus in children has good clinical effect, with many advantages such as a little injury, short hospitalization time, faster postoperative recovery and less complication etc., and can be used as one of the treatment methods.