The authors experience a rare case of the cervical radiculomyelopathy due to calcification of ligamentum flavum at the level of C4-6 and report it with review of the literature. A 60-year-old woman was admitted, complaining progressive quariparesis, gait disturbance and neck pain. She had been treated with diabetes mellitus and hypertension for several years. On radiologic study, calcification of ligamentum flavum[CLF] at the C4-6 level was demonstrated on cervical spine CT and MR scan. Decompressive laminectomy of the C 4-6 and removal of CLF were performed. During operation, thecal sac was severely compressed by hypertrophic ligamentum flavum and there were tight adhesion between calcified ligamentum flavum and dura. After the operation, her motor function and neck pain improved and she could walk with an assistant.