Pseudomonas aeruginosa，a common gram - negative bacterium in clinical practice，showed inherent or acquired resistance to a variety of antimicrobial agents. Pseudomonas aeruginosa is an important pathogenic mechanism of the secretory system and its virulence factors to promote infection or escape the clearance of the host immune system. It is of great significance to study the pathogenesis of virulence factors in Pseudomonas aeruginosa secretion system for prevention and treatment of infection caused by them.