10.22376/ijpbs.2019.10.1.p1-12 Volume 4 Issue 3 2013 (July - September) Acinetobacter spp. has emerged as a significant hospital pathogen, quickly becoming resistant to commonly used routine drugs. Colistin remains as the only drug of choice for carbapenem resistant Acinetobacter. In our study among 65 strains of Acinetobacter isolated from different clinical samples, 2 strains showed Colistin resistance by Disk diffusion method .It was confirmed by performing minimum inhibitory concentration (MIC) using E-strip. To assess the virulence factor biofilm production was also detected in all strains, the 2 strains which showed extreme drug resistance (being colistin resistant) was also strong biofilm producers. Such strains showing extreme drug resistance and strong biofilm production remain as a great threat.  lessThan br / greaterThan ABHISEK ROUTRAY, ANU M.S AND RADHA MADHAVAN Acinetobacter, Colistin, biofilm, drug resistance. 429-434