Abstract: The aim: To research on the functional mechanism of LPS damaging intestinal mucosa microvascular endothelial cells. The way: Divide the intestinal mucosa microvascular endothelial cells fostered into blank control group and LPS group and further divide each group into four minor groups according to the time: 3h, 6h, 9h, 12h. Add feeding medium into the blank control group while fill 1μg/mlLPS nutrient liquid into LPS group. After that, put them into CO2 incubators and cultivate them statically. Result: The secretion of NO rises obviously and arrives at the peak in three hours before it lowers gradually. The secretion of ET rises rapidly and arrives at the peak in 9 hours, then it begins to lower gradually, however, it always stays at a high level. Conclusion: the functional mechanism of LPS damaging intestinal mucosa microvascular endothelial cells may be that LPS leads to the rise in the secretion of NO and ET.