This research aims to assess drug resistance pattern of Pseudomonas aeroginosa. This study cross-sectional was done on 151 positive culture tests of P. aeroginosa from May 2016 until May 2017 in Shahid Sadoughi and central laboratories of Yazd. In this study the sensitivity was evaluated according to the type of antibiotics and then according to location of sampling, type of the specimen and type of reception. The bacteria had most sensitivity to colistin (92.8 %) and then tobramycin (74.2 %). Also the most resistance was to ceftriaxone (70.4 %). The rate of the bacterial resistance to some types of antibiotics was as follow: cefotaxime (64%), ceftazidime (33.1 %), ciprofloxacin (30.3 %) and meropenem (27.5 %). There were not significant differences between antibiotic sensitivities according to the type of specimen while there were significant differences between antibiotic sensitivities based on the location of clinic.