The invention discloses an application of radix isatidis in preparing medicine curing endotoxemia and an application of radix isatidis particle in preparing medicine curing endotoxemia. The invention is characterized in that: the radix isatidis can directly neutralize and degrade the endotoxin, and can reduce the amount of the endotoxin, and can evidently antagonize DIC biological effect caused by the endotoxin and reduce the thrombosis rate of vital organ organization; simultaneously, the radix isatidis particle can prevent the endotoxin stimulating expression of extension spike protein mRNA for vital organ membrane structure of mouse, and can reduce the activity increasing degree of p38 mitogen activited protein kinase induced by the endotoxin.