Background: Biofilms have been defined as complex microbial assemblages anchored toabiotic or biotic surfaces. This microbial assemblage may harbor single or multiplemicrobial populations or micro colonies. Biofilms play a pivotal role in device relatedinfections (DRIs). Formation of biofilm on medical devices is a growing problem.Objectives: we aimed to compare between the minimal biofilm eradication concentration(MBEC) of sessile cells of biofilm forming isolates and minimal inhibitory concentration(MIC) of their planktonic counterpart in device related infections. Methodology: Thisstudy was conducted on 90 patients divided into three groups according to deviceassociated health care associated infections (DA-HAI). Group I included 30 patientswith central line-associated blood stream infection (CLABSI), group II included 30patients with catheter associated urinary tract infection (CAUTI), and group III included30 patients with ventilator associated pneumonia (VAP). Detection of biofilm formationwas done using tissue culture plate and antibiotic susceptibility of biofilm formingbacterial isolates was done by disc diffusion method. MIC and MBEC were done only forbiofilm forming isolates. Results: Out of 79\90 bacterial isolates, 23 isolates (29%) werebiofilm forming. There was statistically significant difference between MIC and MBECof vancomycin and levofloxacin tested for gram positive biofilm forming bacterialisolates (p<0.05) and between MIC and MBEC of imipenem and levofloxacin. For bothgram positive cocci and gram negative bacilli; isolates which were sensitive orintermediately sensitive in the MIC values showed resistance in their MBEC values.Conclusion: The difference between MBEC and MIC was statistically highly significant.Thus, it is recommended to detect MBEC rather than MIC to antimicrobials fortreatment of DRIs.