Intoxication caused by inhalation of nitrous gas, although not well-known in Japan, tends to occur in persons engaged in fire-extinguishing welding, plating, etc. We encountered a 64-year old man working in the plating industry for whom a diagnosis of adult respiratory distress syndrome (ARDS) was carried out. The patient inhaled nitrous gas during a plating extraction process after inserting an aluminum rod with nickel plating in a mixed solution of nitrous and sulfuric acid. Subsegumently, severe dyspnea and a compressive feeling in the chest appeared. A near-by general practitioner diagnosed acute pulmonary edema and transferred him to the emergency center of our hospital for intensive care. Treatment consisted of administering a surfactant for an artificial lung to maintain peak inspiratory pressure (PIP) and prevent pulmonary cavity collapse, and to ameliorate atelectasis and methyl prednisolone to prevent the release of various chemical mediators. The patient showed good progress and was discharged to a general ward on day 14. The onset of pulmonary disorder is not uncommon following intoxication caused by nitrous gas inhalation; prevention is especially important for the disease. It is considered crucially important to maintain good working conditions and to arrange a protective system in addition to making the general public aware of the disease.