developing country like Pakistan. This is an observational study conducted for a period of ten months which ended on December 2013 at the Dr. Essa Laboratory and Diagnostic Centre in Karachi. A total of 4668 urine samples of UTI patients were collected and standard microbiological techniques were performed to identify the organisms in urine cultures. Antibiotic susceptibility testing was performed by Kirby-Bauer technique for twenty five commonly used antimicrobials and then analyzed on SPSS version 17. P. aeruginosa was isolated in 254 cultures [5.4%] . The most resistant drugs included Ceclor [100%] and Cefizox [100%] followed by Amoxil/Ampicillin [99.6%] , Ceflixime [99.6%] , Doxycycline [99.6%] , Cefuroxime [99.2%] , Cephradine [99.2%] , Cotrimoxazole [99.2%] , Nalidixic acid [98.8%] , Pipemidic acid [98.6%] and Augmentin [97.6%] . Emerging resistant strains of Pseudomonas aeruginosa are potentially linked to injudicious use of drugs leading to ineffective empirical therapy and in turn, appearance of even more resistant strains of the bacterium. Therefore, we recommend culture and sensitivity testing to determine the presence of P. aeruginosa prior to specific antimicrobial therapy