Background: Bone metastases in castration resistant prostate cancer (CRPC) is associated with serious morbidity and costs. The optimal timing of initiation and duration of bone targeted therapy (BTT) Zoledronic acid and Denosumab is unknown in the current era with four classes of therapy for CRPC prolonging overall survival (OS). We sought to define the practice patterns of BTT use and outcomes (skeletal related events - SRE and OS) in a high-volume center in the modern era of metastatic CRPC management. Methods: A retrospective cohort of patients (pts) who have received Abiraterone and/or Enzalutamide for CRPC from 2007 to 2017 was identified based on a single-institution’s clinical database. The database and electronic medical record review was used for data collection, including pts’ characteristics and pattern of BTT uses. Kaplan Meier method and Cox proportional hazards model assessed association of BTT use with time to first SRE and OS, respectively. Results: 197 pts were identified, and 79(40%) had ≥ 4 bone metastases (BM) and median follow-up was 4.7 (95%CI: 4.2-5.9) years. More pts with ≥ 4 BM received BTT with first line therapy (49% vs 32% - p-int < 0.01). Pts with ≥ 4 BM, receiving BTT with first line therapy for CRPC had a 19% reduced risk of developing SRE - HR 0.81 (95%CI: 0.45-1.45). Pts with < 4 BM did not have a lower HR when starting BTT with first line CRPC therapy. No OS difference was noted in pts who received BTT with first line therapy or not, regardless of the volume of bone metastases. Conclusions: Our cohort suggested that in the modern era, with more effective and greater number of CRPC therapies, pts with ≥ 4 BM still benefit from starting BTT with first line CRPC therapy.