Bacterial flagellum is the organ of bacterial movement, Helicobacter pylori can pass through the mucus layer on the gastric epithelial cells from the strongly acidic gastric lumen to reach the neutral environment of the gastric epithelial cells, which is a good example of the role of flagellar movement, through the flagellar staining can be observed in the flagellar morphology, the number of flagella and flagellar distribution in the body of the bacterium, the number of flagellum and the distribution of the location of the flagellum in the body of the bacterium is one of the important bases of identification of the bacterium.

The flagellar staining solution adopts the method of carbolic acid compound red, the advantage of this staining method is that it adopts carbolic acid compound red as the core dye, the reagent is more stable, the operation is simple, and the results are more reliable.