Abstract: Background: Acinetobacter baumannii has emerged as an important and problematic nosocomial pathogen. It is responsile for most of infections associated with medical devices, e.g. vascular catheters, cerebrospinal fluid shunts or Foley catheters. It causes several types of infections including pneumonia, meningitis, septicemia, and urinary tract infections. Carbapenems are the drug of choice for treatment but now resistance to these group of drugs is spreading. Mechanism of resistance may be due to production of carbapenemase enzyme or due to biofilm production.