With a rabbit model, the present study was performed to examine the effect of Escherichia coli lipopolysaccharide (E. coli LPS) on hormones. Cortisol, epinephrine, and norepinephrine concentrations in LPS-treated groups were high at all sampling periods (from 3 hrs to 72 hrs) as compared to control group (p$lt;0.05 or p$lt;0.01). The each peak time was at respectively 24 hrs, 3 hrs, and 12 hrs. Insulin and glucagon concentrations in LPS-treated groups elevated up to 12 hrs (p$lt;0.01 or p$lt;0.05) with a each peak point at 12 hrs or 6 hrs, while those of the rest sampling points (from 24 hrs to 72 hrs) were lower than that of control (p$lt;0.05). Increase of cortisol concentration was generally dose-dependent, whereas the changes of the other hormones were irregular patterns. These observations show that E. coli LPS lead to releases of stress hormones such as cortisol, epinephrine, and norepinephrine and disturbances of endocrine systems. These LPS-induced hormonal disorders may cause physiologically fatal results.