A 63-year-old woman with amyotrophic lateral sclerosis (ALS) was scheduled for open reduction and internal fixation of the right tibia. Total intravenous anesthesia using propofol and remifentanil without muscle relaxant was selected as the anesthetic method, in order to avoid the possible occurrence of ventilatory depression due to abnormal responses to muscle relaxants and exacerbation of the motor neuron disease. After standard and neuromuscular monitoring devices were applied, anesthesia was induced and maintained with target controlled infusion of propofol and remifentanil in the range of 2.5-5.0 microg x ml(-1) and 2.5-5.0 ng x ml(-1), respectively. To avoid delayed neuromuscular recovery, we did not use any muscle relaxant at all. Intubation was successful and there were no remarkable events during anesthesia, except for three brief hypotensive events; there was no exacerbation of ALS itself during or after the anesthesia. She was discharged on postoperative day 3, without any discomfort.