BackgroundData on functional and psychological side effects following curative treatment for prostate cancer are lacking from large, contemporary, unselected, population-based cohorts. ObjectiveTo assess urinary symptoms, bowel disturbances, erectile dysfunction (ED), and quality of life (QoL) 12 mo after robot-assisted radical prostatectomy (RARP) and radiotherapy (RT) using patient-reported outcome measures in the Swedish prostate cancer database. Design, setting, and participantsThis was a nationwide, population-based, cohort study in Sweden of men who underwent primary RARP or RT between January 1, 2018 and December 31, 2020. Outcome measurements and statistical analysisAbsolute proportions and odds ratios (ORs) were calculated using multivariable logistic regression, with adjustment for clinical characteristics. Results and limitationsA total of 2557 men underwent RARP and 1741 received RT. Men who underwent RT were older (69 vs 65 yr) and had more comorbidities at baseline. After RARP, 13% of men experienced incontinence, compared to 6% after RT. The frequency of urinary bother was similar, at 18% after RARP and 18% after RT. Urgency to defecate was reported by 14% of men after RARP and 34% after RT. At 1 yr, 73% of men had ED after RARP, and 77% after RT. High QoL was reported by 85% of men after RARP and 78% of men after RT. On multivariable regression analysis, RT was associated with lower risks of urinary incontinence (OR 0.25, 95% confidence interval [CI] 0.19–0.33), urinary bother (OR 0.79, 95% CI 0.66–0.95), and ED (OR 0.54, 95% CI 0.46–0.65), but higher risk of bowel symptoms (OR 2.86, 95% CI 2.42–3.39). QoL was higher after RARP than after RT (OR 1.34, 95% CI 1.12–1.61). ConclusionsShort-term specific side effects after curative treatment for prostate cancer significantly differed between RARP and RT in this large and unselected cohort. Nevertheless, the risk of urinary bother was lower after RT, while higher QoL was common after RARP. Patient summaryIn our study of patients treated for prostate cancer, urinary bother and overall quality of life are comparable at 1 year after surgical removal of the prostate in comparison to radiotherapy, despite substantial differences in other side effects.