The changes of selenium metabolsim, glutathione peroxidase acivity and lipid peroxides content in the tissues of rats suffering from 30% TBSA full thickness scalding were observed in the first 7 days after injury. It was found that selenium content in the rat tissues decreased remarkably after injury,which in turn resulted in serious reduction of glutathione peroxidase activity and significant increase of lipid peroxides in the serum, erythrocytes and liver. However the muscular tissue showed no significant changes.These facts imply that after burn injury, the body is in a state of selenium deficiency, the loss of selenium might be responsible for the reduction of anti-peroxidation ability of glutathione peroxidase, and consequently there is an increase of lipid peroxides in the tissues. Only the muscular tissue is insensitive to lipid peroxiation. It is believed that the reduction of anti-peroxidation ability of glutathione peroxidase after burn injury might be one of the main causes to intensify the injury resulting from free radicals.