A man who worked in the synthetic leather manufacturing plant for 3 months died at November 3. Author review the medical record, the death certificate, and interviewed his wife and the doctor who treated him. His major job was DMF handling. At the working place, he felt severe health problem, and admitted to the hospital via emergency clinic. He complained severe abdominal pain and showed jaundice and ascites, He suffered hepatic coma and respiratory insufficiency from fulminant hepatitis from 19th days after admission. Drug abuse, hepatitis (A, B, C), and alcoholic hepatitis were rule out with his history and serological study data, As a result, author couldn't find any cause of death, but fuIminant hepatitis from DMF toxicity.