Objective    To observe the effect of arthroscopic meniscectomy for symptomatic discoid lateral meniscus and the importance of early treatment.     Methods    Arthroscopic meniscectomy was performed on 29 patients (31 knees) with symptomatic discoid lateral meniscus. Partial meniscectomy was performed on 27 knees

subtotal meniscectomy on 4 knees with tear on the edge of meniscus.     Results    The operations on all 31 knees were successful without complications. The mean Lysholm score was 95.6 (87-100) during the follow-up

which was significantly higher than that before the operation (65.7

range 36-78; P0.01). The mean Lysholm score in the patients under 20 years old (mean 97.2

range 94-100) was significantly higher than the patients over 20 years (mean 93.7

range 87-100; P0.01).     Conclusion    Arthroscopic meniscectomy is effective in managing symptomatic discoid lateral meniscus. The early treatment can achieve better outcomes for the patients with symptomatic discoid lateral meniscus.