Bacterial lipopolysaccharide (LPS) is a component of the outer wall of the cell wall of Gram-negative bacteria. It is a substance (glycolipid) composed of lipids and polysaccharides. Bacterial LPS or bacterial endotoxin can cause endotoxemia, sepsis, and other diseases. Due to the relationship between LPS and sepsis, the study of lipopolysaccharide is particularly important, while antibodies and inhibitors of LPS biosynthesis have become possible targets that cannot be ignored.