OBJECTIVES: Conduct a pharmacoeconomic analysis, cost-minimization type of therapy with linezolid in patients hospitalized between August, 2009 and December, 2010 in a public hospital in Brazil. METHODS: We conducted a retrospective cohort study at a Brazilian public hospital from August 1, 2009 through December 31, 2010. A cost-minimization analysis was undertaken for which patients used linezolid during the internment in this period, from the perspective of the Brazilian public health system. RESULTS: The medical records of 61 patients were evaluated. Of all patients, 67.2% were male and mean age was 43.2 ± 17.8 years. The therapy with linezolid lasted 10.6 ± 4.7 days. The antibiogram was present in 65.6% of the records. In 50.8% of cases, the bacteria were sensitive to linezolid. The main reason for the use of antibiotics was sepsis and nosocomial pneumonia (34.4% each). Sixteen (26.2%) patients met the criteria for changing the route of administration of the antimicrobial. Altogether, the cost of treatment with linezolid for these 16 patients was US$ 39.755,05. If it were adopted sequential therapy, the treatment would cost US$ 31.744,28, which represents a saving of US$ 8.010,77 to the hospital. CONCLUSIONS: The results demonstrated the importance of pharmacoeconomic analysis of linezolid to the hospital, because in 17 months of cost analysis, these could have been reduced by 20,2% only with the switch antibiotic therapy. It is expected that results of studies such as this may contribute to the rational use of antimicrobials and resources for hospitals.