Background: Metastatic castration-resistant prostate cancer (mCRPC) occurs in men with advanced disease progressing to androgen deprivation therapy, with serum testosterone < 50 ng/dL. In this setting, several active therapies are available, such as chemotherapy and androgen receptor-targeted agents. We analyzed the efficacy of the carboplatin - paclitaxel (C-P) combination in mCRPC patients after several lines of treatment. Methods: In this retrospective observational study, we analyzed the clinical data of 43 patients with mCRPC who received treatment with biweekly C-P between 2015-2022 at the Hospital Universitario Virgen de Valme. The data collected refer to the baseline characteristics of the patients at the start of treatment (age, functional status), stage at diagnosis and treatments received in first and successive lines, among others. The response variables analyzed were both overall survival (OS) and progression-free survival (PFS). Treatment-derived toxicity was collected. The data were processed with IBM-SPSS Statistics v. 25. The information was collected from Diraya Estación Clínica v 4.0.80 and Farmis-Oncofarm. Results: As of September 2022, data had been collected for 43 men with mCRPC. Histology was adenocarcinoma in all cases. At the start of C-P treatment: 48.9% of patients were in good functional status (ECOG ≤ 1), median age was 71 years and 62.8% had received at least 3 lines of treatment. Patients received C-P for a median of 12 weeks: 76.7% showed clinical improvement and 44.2% had PSA decline, with PSA decline ≥ 30% in 27.5% of patients. The median OS (mOS) was 8 months (95% CI 6.46-9.54) and the median PFS was 14 weeks. By Kaplan-Meier survival analysis, we compared mOS as a function of PSA: response/non-response, the differences being statistically significant: 11 (95% CI=6.22-15.78) vs. 6 (95% CI=4.21-7.79) months, respectively (Log Rank 0.001). The main toxicity was hematological. Conclusions: The C-P combination may be an effective treatment option in patients with mCRPC refractory to various lines of therapy, with PSA being a good marker of response to treatment.