This nationwide register-based cohort study examined the association between castration status and postoperative survival in men who had undergone surgery for spinal metastases from prostate cancer. Bone metastases are common in prostate cancer, with the spine being the most frequent site. Using data from the Swedish Spine Register (Swespine) and Prostate Cancer Database Sweden (PCBaSe), 306 men with prostate cancer who underwent spinal surgery were identified. In total, 81 were categorized as castration-sensitive and 225 as castration-resistant disease at the time of spinal surgery. Postoperative survival was estimated using Kaplan-Meier analysis and compared with the log-rank test. Multivariable Cox regression was used to adjust for potential confounders. Median survival after surgery was significantly longer in men with castration-sensitive prostate cancer (33 months, IQR 15-55) compared to those with castration-resistant disease (8 months, IQR 5-31; p < 0.001). Castration-sensitive status was independently associated with a lower risk of death (hazard ratio 0.29, 95% CI: 0.20-0.41). These findings indicate that castration sensitivity is a strong prognostic factor for survival after surgery for spinal metastases from prostate cancer and should be considered in surgical decision-making.