Glutaric aciduria (GTA) type II can be seen as late onset form with myopathic phenotype. We present a case of a 19-year old female with progressive muscle weakness was admitted in intensive care unit (ICU) with respiratory failure and acute renal failure. Patient was unconscious. Pupils were anisocoric and light reflex was absent. She had hepatomegaly. The laboratory results showed a glucose level of 70 mg/dl and the liver enzymes were high. The patient also had hyponatremia (117 mEq/L) and lactate level of 3.9 mmol/L. Tandem MS and organic acid analysis were compatible with GTA type II. Carnitine 1gr, riboflavin 100 mg and co-enzymeQ10 100 mg was arranged. After four months from beginning of treatment tandem MS results are improved.