Objectives To perform a budget impact analysis (BIA) of introducing olaparib as maintenance therapy in women who have BRCA mutations (BRCAm) with platinum-sensitive recurrent ovarian cancer (PSROC) in combination with bevacizumab in Argentina.Methods A BIA model was used to analyse over a 5-year time horizon the change in the health system's budget following the adoption of olaparib as maintenance therapy in BRCAm patients with PSROC. The BIA for each year was estimated by comparing the cost difference between the current scenario (treatment with bevacizumab) and the new scenario (the addition of olaparib) for a third-party payer. The BIA is estimated at the national health system level, and by healthcare sectors in Argentina (public sector, social security and private sector). International and national epidemiological data were used to determine the target patient population. Clinical efficacy, safety outcomes and duration of treatments were obtained from the pivotal clinical study report. Relevant direct medical costs were obtained from public data in Argentina and expert consultation. All the costs are reported in US dollars as of October 2022 ($1 = 152.59 Argentine pesos). A scenario analysis assessed the full coverage of the homologous recombination deficiency (HRD) test in Argentina. In addition, one-way sensitivity analysis was conducted to evaluate the model robustness.Results For a third-party payer with a cohort of 1,000,000 women covered, the estimated target population was 2 individuals in year 1 and 6 individuals in year 5. The incorporation of olaparib, with a wholesale price per pack of $3176.32, was associated with a weighted average of the budget impact per member per month (PMPM) of $0.062 for the national health system, being above the estimated health system budget impact threshold ($0.0153). By healthcare sector, the results of budget impact PMPM for year 5 ranged between $0.08 (public sector) and $0.114 (private sector). For all perspectives, the variables that most influenced the budget impact was the incidence of ovarian cancer, the drug acquisition cost and the treatment duration.Conclusions The introduction of olaparib for the treatment of BRCAm women with PSROC has a high budget impact for all three health systems in Argentina.