OBJECTIVES: Prostate cancer is the most frequent malignant tumor in the Costa Rican male population. To date, in the CCSS there is not available any antitumor therapy for patients with metastatic castration resistant prostate cancer (mCRPC), with progression after receiving chemotherapy with docetaxel. This research aims to evaluate the cost/effectiveness (and cost/utility) of Abiraterone in the treatment of patients with mCRPC, with disease progression after chemotherapy treatment based on docetaxel, compared with only giving palliative care, from the perspective of CCSS. METHODS: Markov Model, designed to estimate the ICER and ICUR of treatment with Abiraterone compared to only giving prednisolone. It considers a cohort of 50 patients based on epidemiological information in Costa Rica.  Health states: Stable disease, progressive disease and death. Probabilities for transition were based on COU-AA-301 Study. Time horizon is 10 years.  Cycle longitude is 3 months.  Efficiency threshold is $30.000. Discount rate is 3%. Costs expressed in 2015 US dollars. The resources needed for the care were obtained from expert consultation following the Delphi Method. The costs of resourses were obtained from the CCSS tariff model. We used ex-factory prices of abiraterone. RESULTS: Treating with abiraterone plus prednisolone requires an additional investment of $36,691.51; produces 0.81 additional LYG and additional 0.47 QALY gained. The ICER (ICUR) was estimated in $78,077.23/QALY. The most sensitive parameters modifying the results of the model in the one-way sensitivity analysis are the utility value assigned to the health state progressive disease, and medication price. After running one thousand iterations of the probabilistic sensitivity analysis, the average ICUR was $80,203.42 per QALY gained. CONCLUSIONS: Given the conditions of Costa Rica’s economy, and the results of the current study, offering treatment with abiraterone to patients with mCRPC is not an efficient intervention, compared to giving only prednisolone and palliative care.