Abstract: OBJECTIVE To investigate the anti-lipopolysaccharide(LPS) activity of jasminoidin in vitro and in vivo. METHODS The binding activity of jasminodin to Lipid A and the neutralization on LPS were detected by the biosensor technology and kinetic turbidimetric limulus test. Meanwhile, ELISA was used to measure the release of cytokine from RAW264.7 cells exposure to LPS with or without pretreatment of jasminoidin. Furthermore, the protective effect on mice subjected to lethal dose of LPS challenge with or without treatment of jasminoidin was observed. RESULTS Jasminoidin had binding activity to Lipid A and significantly neutralized LPS(0.1 μg·L^-1) in dose of 2.5, 5.0, 10.0 mg·L^-1(P<0.01). Subsequently, the release of TNF-α from RAW264.7 cells exposure to LPS(100 μg·L^-1) was significant attenuated by pretreatment with jasminoidin in the dose of 50, 100 mg·L^-1(P<0.01). In vivo experiment, jasminoidin could significant protect mice against a lethal challenge with LPS at the dose of 40 mg·kg^-1(P<0.01). CONCLUSION Jasminoidin can neutralize LPS and suppress the activating of RAW264.7 cells induced by LPS. In vivo, jasminoidin can significantly protect mice against a lethal challenge with LPS. Jasminoidin has anti-lipopolysaccharide activity.