OBJECTIVE To report a case of cefotetan disodium-induced hemolytic anemia. METHODS Original research articles and case reports. RESULTS A 46-year-old woman developed fulminant hemolytic anemia following a second exposure to intravenous cefotetan disodium for postoperative prophylaxis. She developed respiratory failure requiring intubation and acute renal failure requiring hemodialysis. The hemolysis was successfully treated with plasmapheresis, but the patient died on the 25th postoperative day. Positive Coomb's tests have been reported in less than three percent of patients receiving cefotetan. To our knowledge, this is the first case of fulminant hemolytic anemia associated with intravenous cefotetan disodium therapy. CONCLUSIONS Cefotetan should be added to the list of drugs known to cause hemolytic anemia. Monitoring for hemolysis should be considered for patients who receive multiple courses of therapy.