Background and Objective: Pseudomonas aeruginosa is an opportunistic pathogen causing nosocomial burn infections. Disease results from the production of numerous virulence factors, some of which are injected directly into the eukaryotic host cells via the type III secretion system (T3SS).The aim of this study was to determine the prevalence of cytotoxins encoding exoT, exoY, exoS and exoU genes among the P. aeruginosa isolated from burn patients. Materials and Methods: Over one year period of study, a total of 95 isolates of P. aeruginosa were collected and identified from burn infections in hospitalized patients. Polymerase chain reaction (PCR)-based method was used for detection of exoT, exoY exoS and exoU genes. According to CLSI (Clinical Laboratory Standards Institute) guidelines antimicrobial susceptibility testing was performed by disc diffusion method against 10 antibiotics. The data were analyzed by χ2 test. A p value of <0.05 was considered as statistically significant. 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