We report the successful treatment of refractory cancer pain by bilateral intrathecal neurolysis using phenol-glycerol. A 60-year-old man had recurrent sigmoid cancer and metastases to the lumbar (L4-5) and sacral bones. He complained of refractory pain in the lower back and lower extremities despite high-dose opioid treatment based on the WHO ladder. On admission to our hospital, he received continuous intravenous infusion of morphine (7,000 mg/day) with ketamine (300 mg/day) and lidocaine (700 mg/day). Intravenous midazolam was required to treat extreme anxiety. Because of inadequate pain relief and severe drowsiness, intrathecal phenol-glycerol neurolytic block was performed twice at the L2/3 intervertebral space. His analgesia was greatly improved and high-dose intravenous opioid was retitrated and ceased. He remained comfortable and lucid at home for 2 months, until 2 days before his death at hospital. Intrathecal neurolytic block may be appropriate for some patients suffering from refractory pain that is resistant to conventional opioid analgesic treatment.