Neuroleptic malignant syndrome is one of the side effects of neuroleptic drugs characterized by high fever, autonomic dysfunction, tremors and muscle rigidity. A 41-year-old man who had been hospitalized with schizophrenia for 14 years demonstrated worsening of his psychic state. Neuroleptic drugs were administered. About 1 year later, he was admitted to Isesaki Municipal Hospital presenting hyperthermia, nausea and cough and was diagnosed as having pneumonia and acute renal failure. We performed emergency hemodialysis for treatment of acute renal failure and administered antibiotics for aspiration pneumonia. Due to fluctuating consciousness, general muscle rigidity, hyperhidrosis, hypertension and tremors, neuroleptic malignant syndrome with acute renal failure was suspected. Therefore, he was given dantrolene sodium (60mg/day p.o.), but his symptoms did not improve. After he received sodium valproate (600mg/day p.o.) and trihexyphenidyl hydrochloride (6mg/day p.o.), the muscle rigidity and tremors disappeared. We noticed improvement of his general state following medication and hemodialysis. After we switched to diazepam (6mg/day p.o.) and bromocriptine mesilate, his psychological state normalized. Immediate hemodialysis was considered effective for treatment of neuroleptic malignant syndrome with acute renal failure.