Abstract: Objective:Prostate cancer frequently metastasizes to the spine. In this study, we investigate the prognostic factors as -sociated with survival in patients with prostate cancer accompanied by spinal metastases at their preliminary diagnosis. Methods:Clin -ical data of 49patients who were diagnosed with spinal metastasis from prostate cancer between January 2005and December 2010 were analyzed. Variables including alkaline phosphatase (ALP), previous skeletal-related event, Gleason score, prostate-specific anti-gen (PSA) nadir, and time to castration resistance were obtained. Moreover, the relationship between these variables and overall sur-vival (OS) was analyzed. Survival analysis was performed by using Kaplan-Meier curves. Furthermore, the differences among the OS rates were assessed by using the log rank test. The variables were statistically significant in the univariate analysis ( P<0.05) and were included in the multivariate model. Results: The average follow-up time was 64.1 months among the 49patients. By the end of the follow-up, 41of these patients were dead; the mean survival was 27months. The1-, 3-, and 5-year survival rate was 81.6%,40.8%, and 20.4%, respectively. Univariate analysis identified that 6 variables were statistically significant prognostic factors of OS: with or without chemotherapy, ALP, previous skeletal-related event, Gleason score, PSA nadir, and time to castration resistance. The multivari-ate analysis showed that the time to castration resistance of ≥ 19months and the addition of chemotherapy after disease progression are independent prognostic factors for a high OS. Conclusion:With or without chemotherapy and the time to castration resistance are the independent prognostic factors associated with survival in patients with prostate cancer accompanied by spinal metastases at first diagnosis.