Objective To analyze the virulence genes expression and drug resistance situation of type three secretion system (TTSS) of pseudomonas aeruginosa in Zhongshan area to provide a basis for clinical anti-infection treatment .Methods Seventy-six clinically isolated strains of Pseudomonas aeruginosa were collected from the Zhongshan Municipal People′s Hospital from July to September 2016 .Four virulence genes exoU ,exoS ,exoT and exoY were isolated from the strains by PCR .The Vitek2 Compact au-tomatic microbiological identification instrument was used to detect the sensitivity of antibacterial drugs .The enumeration data were processed with chi-square test .Results The detection rates of gene exoS and exoY were highest ,which were 52 .6% (40/76) and 63 .2% (48/76) respectively ;genotype exoU(-)exoS(+ )exoT (-)exoY(+ ) were predominant and accounted for 59 .26% .The positive rates of 4 virulence genes had no statistical difference between the multiple resistant and non-multiple resistant strains of pseudomonas aeruginosa .The resistance rates in the TTSS positive group to 13 kinds of drugs were commonly lower than those in the TTSS negative group ,the difference was statistically significant .Conclusion The geographic difference exists in virulence genes carrier of pseudomonas aeruginosa .The virulence genes carrying situation in both the multiple resistant and non-multiple resistant strains of pseudomonas aeruginosa is similar .