A 74-year-old male was admitted to hospital with acute rhabdomyolysis and myoglobinuria due to hypokalemia. The hypokalemia resulted from diuretic treatment. He had no family history of myopathy, and no diarrhea and vomiting. The neurological examination revealed painful quadriplegia. The blood pressure was 160/74 mm Hg. Laboratory examination showed hypokalemic and hypochloremic metabolic alkalosis (serum K 1.5 mEq/l, serum Cl 89 mEq/l, base excess + 20.9, HCO3- 44.9 mmol/l, pH 7.563) and marked elevations of serum CPK, LDH, GOT, GPT and myoglobin. Endocrinological and renal functions were normal. Muscle biopsy revealed marked necrosis with remarkable phagocytosis and vacuolar degeneration. The cessation of diuretics and intravenous infusion of potassium chloride resulted in a marked improvement in clinical and laboratory findings. The diuretics-induced hypokalemic myopathy is rare in the literature.