OBJECTIVE: To provide a better treatment method of lumbar stenosis and root pain resulting from simple hypertrophy of ligamentum flavum. METHODS: By studying the records of 143 lumbar pain cases, we found 5 cases caused by simple hypertrophy of ligamentum flavum. All the patients were old man with a long progressed history. There was little difference of clinical features between the disc herniation and hypertrophy of ligamentum flavum. All cases accepted resection of ligamentum flavum. RESULTS: All the symptoms were relieved postoperatively. The patients could walk. CONCLUSION: The degeneration of lumbar ligamentum flavum can cause lumbar stenosis and root pain. Resection of ligamentum flavum can relieve the symptom.