Background: Pseudomonas aeruginosa is a common cause of nosocomial infections with rnassociated morbidity and mortality because the organism is unresponsive to commonlyrnavailable antimicrobials. This study was undertaken to determine the Multiple Drug-Resistantrn(MDR), Extensive Drug-Resistant (XDR) and Pan Drug-Resistant (PDR) phenotype ofrnP.aeruginosa and its carbapenemase production rate from presumptive isolates stored in thernbio-bank at the Ethiopian Public Health Institute (EPHI). rnMethods: A cross-sectional study was conducted at the EPHI laboratory, Addis Ababa,rnEthiopia from March to June 2021. Stored isolates of Pseudomonas spp. which had beenrncharacterized by manual identification methods were further processed for species-levelrnidentification (ID) and antimicrobial susceptibility testing (AST) using a Becton Dickinsonrn(BD) Phoenix automated system. The isolates were analyzed for carbapenemase enzymernproduction using the modified Carbapenem Inactivation Method (mCIM). The data analysisrnwas done using SPSS version 20 software. rnResults: In this study, 110 presumptive Pseudomonas isolates from a biobank were reanalyzed,rnrn100 of them were found to be Pseudomonas and among these P.aeruginosarnaccounted for 98% and P.putida accounted for 2%. The majority of isolates were recoveredrnfrom wound (46%) specimens followed by ear swabs (18%). The highest level of resistancernwas observed against Ceftazidime (35%) and the lowest level of resistance was observedrnagainst Amikacin (2%). Twenty-seven isolates were identified as candidates forrncarbapenemase enzyme production testing, of which only 3/27 (11%) isolates were detectedrnas carbapenemase enzyme producers. rnConclusions: This study shows an increasing rate of MDR and XDR isolates and thernappearance of PDR in P.aeruginosa strain, this is a serious problem in Ethiopia. The lack ofrnnewer anti-pseudomonal antibiotics adds to the problem. In order to alleviate this problem, rnInfection prevention activities should be promoted, and treatment of bacterial infectionsrnshould be guided by antibiotic susceptibility test results.