Purpose: To evaluate the validity of the Gleason score after neoadjuvant hormonal treatment as predictor of disease-specific mortality after radical prostatectomy. Patients and Methods: A total of 2,880 patients with a complete data set and a mean follow-up of 10.3 years were studied; 425 of them (15%) had a history of hormonal treatment prior to surgery. The cumulative incidence of deaths from prostate cancer was determined by univariate and multivariate competing risk analysis. Cox proportional hazard models for competing risks were used to study combined effects of the variables on prostate cancer-specific mortality. Results: A higher portion of specimens with a history of neoadjuvant hormonal treatment were assigned Gleason scores of 8-10 (28 vs. 17%, p < 0.0001). The mortality curves in the Gleason score strata <8 vs. 8-10 were at large congruent in patients with and without neoadjuvant hormonal treatment. In patients with neoadjuvant hormonal treatment, a Gleason score of 8-10 was an independent predictor of prostate cancer-specific mortality; the hazard ratio was, however, somewhat lower than in patients without neoadjuvant hormonal treatment. Conclusion: This study suggests that the prognostic value of the post-radical prostatectomy Gleason score is not meaningfully jeopardized by heterogeneous neoadjuvant hormonal treatment in a routine clinical setting.