Pseudomonas aeruginosa is a major opportunistic pathogen in clinic and can produce a variety of virulence factors and high antibiotic resistance. Type III secretion system (T3SS) is an important virulence factor secretion system that facilitates the delivery of bacterial effector proteins into eukaryotic host cells. Successful evasion of phagocytosis and subversion of normal host cell physiology to promote pathogenesis depend primarily on the presence of T3SS. Research on T3SS will help us understand the pathogenesis of P. aeruginosa and provide a theoretical basis for clinical treatment and the development of novel antipathogenic drugs. In this review, the structure, function, regulation mechanism and targeted treatment of T3SS in P. aeruginosa are discussed.