Knee joint-related symptoms are frequent and the use of MRI as a diagnostic tool is common. About 25% of MRIs show meniscal degeneration (MD). As the natural history of MD has not been well described, we studied the long-term outcome of 50 MDs. 45 patients were initially evaluated by a MRI, and clinical examination and later by another MRI. After 5 years, 38 of the MDs were unchanged, 8 had progressed and 4 regressed. Progression of MD was associated with age over 40 years, trauma during the follow-up period and/or other knee lesions, such as osteoarthrosis and ligament rupture. The clinical findings were consistent with MDs only in 8 cases.