Tetanus is a potentially fatal infection. Approximately 100 cases are reported in Japan each year; however, little is known about its clinical course and outcomes in the current era of treatment. We herein report three cases of tetanus in elderly patients who survived after mechanical ventilation and intensive care. These patients, together with six other similar cases, had a median weaning period of 31 days and median length of stay of 77 days. In elderly patients, severe systemic forms of tetanus require prolonged mechanical ventilation and hospitalization. To improve prevention, tetanus vaccination should be promoted more aggressively among those who are susceptible to the disease.