Many organic and nonorganic agents can cause chemical pneumonitis. Chemical pneumonitis induced by inhalation of acetic acid is a rare clinical condition. As acetic acid is a water soluble agent, it causes chemical irritation to respiratory tract and causes variable symptoms. We experienced a case of acute lung injury due to inhalation of acetic acid fume. A 56-year-old male patient was admitted due to dyspnea with vomiting for one day. After he inhaled acetic acid fume in occupational situation, he had chest tightness, chilling sense, and productive cough. Our case was good response to oxygen inhalation, antibiotics, and systemic steroids.