Pseudociliated columnar epithelium consists of columnar cells, squamous cells, and cone-shaped cells, which are distributed on the inner surface of the respiratory tract and have the function of removing foreign bodies from the respiratory tract. Pseudocomposite ciliated columnar epithelium is called pseudocomposite because it is a combination of multiple cells, which appear at different heights and have differently positioned nuclei, forming a multilayered distribution in which the base of each cell is attached to the basement membrane. In addition, columnar epithelial cells can reach the free surface while wiggling their microvilli, hence the term pseudocomplex microvillous columnar epithelial cells. Pseudocomplex ciliated columnar epithelial cells are distributed on the mucosal surface of the respiratory system, and there are many mucus-secreting cup cells distributed between the columnar epithelial cells. The mucus secreted by the cells can moisten the dry air and adsorb dust, bacteria, and viruses from the respiratory tract, and with the wiggling of the villi of the columnar epithelial cells, the foreign matter is cleared to the pharynx. In summary, the pseudocomplex microvilli columnar epithelial cells can effectively provide security to the organism, as well as assist in clearing the respiratory system and assist in warding off a number of external disease germ infections.