Objectives: Bladder and prostate cancers occur with increasing prevalence in the ageing population. Our study aims to quantify the incidence of prostate cancer in patients undergoing cystoprostatectomy for bladder cancer and assess the impact of that incidental prostate cancer on oncological outcome. Methods and Materials: We retrospectively reviewed the pathology reports of 128 men who underwent cystoprostatectomy for bladder cancer. Results: Twenty-three men (18%) were found to have incidental prostate cancer. All incidental prostate cancers were organ confined and 91% were well or moderately differentiated. At a mean follow-up of 55 months the prostate cancer-free survival was 96%. Conclusion: The incidence of prostate cancer in cystoprostatectomy specimens is high. When the prostate is removed completely the presence of incidental prostate cancer does not influence the overall oncological outcome.