Few reports have focused on the association between apparent treatment-resistant hypertension (aTRH) and cardiovascular (CV) mortality in peritoneal dialysis (PD) population, thus we conducted this retrospective cohort to explore it.Patients and Methods: This was a retrospective cohort study conducted from January 2011 to January 2020 with PD patients in 4 Chinese dialysis centers. ATRH was defined according to the American College of Cardiology and American Heart Association guidelines. ATRH duration was calculated as the total number of months when patients met the diagnostic criteria in the first PD year. The primary outcome was CV mortality, and the secondary outcomes were CV events, all-cause mortality, combined endpoint (all-cause mortality and transferred to HD), and PD withdrawal (all-cause mortality, transferred to HD and kidney transplantation). Cox proportional hazards models were used to assess the association.A total of 1,422 patients were finally included in the analysis. During a median follow-up period of 26 months, 83 (5.8%) PD patients incurred CV mortality. The prevalence of aTRH was 24.1%, 19.9%, 24.6% at 0, 3, 12 months after PD initiation respectively. Overall, aTRH duration in the first PD year positively associated with CV mortality (per 3 months increment, adjusted HR, 1.29; 95% CI 1.10, 1.53; P=0.002). After categorized, those with aTRH duration more than 6 months presented the highest adjusted HR of 2.92. Similar results were found for secondary outcomes, except for the CV event.Longer aTRH duration in the first PD year is associated with higher CV mortality and worse long-term clinical outcomes. Larger studies are warranted to confirm these findings.© The Author(s) 2024. Published by Oxford University Press on behalf of American Journal of Hypertension, Ltd.