Background:- Ability to develop multiple drugs resistance and biofilm formation have made Acinetobacter species an important hospital-acquired pathogen and a challenge to their effective management. Objective:- Through this study we can isolate different Acinetobacter sps. and study their antimicrobial susceptibility patterns. Isolated resistant Acinetobacter was further analyzed for the detection of Extended-spectrum β-lactamases (ESBLs), Metallo β-lactamases (MBLs), Carbapenemase production. Materials and Methods:- Various clinical specimens which were submitted to the Department of Microbiology, Patna Medical College & Hospital, Patna, Bihar were studied for antibiot ic susceptibility testing, detection of ESBL and MBL production by standard microbiologic a l methods. Results:- The pre-dominant Acinetobacter species isolated was A. calcoaceticus-bauma nnii Complex (Acb complex) 167 (52.1). Among those, all A. species 127 (44.7%) were multidr ug resistant (MDR). In which 12 (4.22%) were ESBL producers and 36 (12.8%) Carbapenemases producers. The majority of A. species were resistant to cefotaxime 72.6% and cefepime 78.4%. Conclusion:- Drug-resistant Acinetobacter formed a substantial proportion of this hospital’s samples. This situation warranted stringent surveillance and adherence to infection prevention and control practices.