Emerging antibiotic resistance in microorganisms particularly multidrugresistant bacterial strains are increasing because of misusing antibiotics as well as the evolution of antibiotic resistance mechanisms in new strains. In this regard, Acinetobacter baumannii is one of the six most common multidrugresistant microorganisms related to nosocomial diseases. Recently, carbapenems, as common antibiotics to treat infections caused by Acinetobacter have not shown an acceptable efficiency because of the resistance emergence to carbapenems in many strains of this bacterium. In this study, resistant strains of A. baumannii were isolated and identified as an appropriate preventive strategy to reduce bacterial infections in al-yarmouk hospital of Iraq. Disc diffusion test and PCR method were used to isolate of resistant strains and identify beta-lactamase genes of blaAmpC, blaTEM, blaVIM, and blaSHV. This study showed that these genes were contributed to the antibiotic resistance with about 18.4% and ≥53.5% strains expressing all 4 genes and ≥3 genes, respectively. The blaAmpC gene is more prevalent than other genes, and this is probably due to the prevalence or rapid transfer of this beta-lactamase. However, more studies should be performed in a comparative way to isolate and identify other antibiotic-resistant bacterial strains associated with other hospitals. Article info