Abstract: A dynamic fumigation system was used to study the relationship of the accumulation of hydrogen peroxide and lipid peroxidation after sulfur dioxide fumigation.SO₂ concentration were 0.5,0.3,0.1,0.05 ppm and control(unfiltered air)respectively.With lower SO₂ concentrtion(0.1,0.05 ppm),there were less accnmulation of H₂O₂ and the lipid peroxidation were lower,while with higher SO₂ concentration(0.5,0.3ppm),the H₂O₂ accumulated sharply, and the lipid peroxidation was higher.Regression analysis indicated a significant positive relation between H₂O₂ content and MDAcontent.