This study was aimed at determining the pattern of usage of antibiotics at Viet-Duc Hospital. Data were retrospectively retrieved from records at Pharmacy, General Planning and Microbiology departments during the period from 2009 to 2011. The annual total antibiotic consumption was high with defined daily dose units per 100 patient-day (DDD100) about of 326,55. The 3rd and 4th cephalosporin generations, penicillin/betalactamase inhibitor combinations, 5-nitro-imidazol derivaties, aminoglycoside and fluoroquinolone antibiotics were the most used antimicrobials. Nosocomial Gram negative pathogens E. coli, Klebsiella pneumoniae, Enterobacter spp., Pseudomonas aeruginosa and Acinetobacter spp. in particularly were highly resistant to currently used antibiotics. These findings suggest that more efforts are needed in establishing antibiotic stewardship at Viet-Duc hospital.