Abstract: Objective In order to study damnification action and action mechanism of toxicity of n-Hexane ofr membrane lipid.Methods The way of exposing in static total enclosure chamber with inhalation n-Hxane for rats was adopted,then the toxicity action was observed.Results The content of GSH and MDA in the blood of the rats and the activity of SOD and GSH-Px in the liver decreased obviously.Observation of morphology showed that the damage of membrane system of the liver was serious.Conclusion Rapid inhalation n-Hxane could results in or promote damage reaction of activity oxygen free radical for ogranism and made the damage of lipid peoxidation.