To examine the association of serum 25-hydroxyvitamin D [25(OH)D] with all-cause mortality and disease-specific mortality in patients with hypertension.This cohort study included US adults in the National Health and Nutrition Examination Survey from 2007 to 2018. All-cause mortality and cause-specific mortality outcomes were determined by association with National Death Index records. Cox proportional risk models were used to estimate hazard ratios (HRs) for all-cause mortality and cause-specific mortality and 95% confidence intervals (CIs) for serum 25(OH)D concentrations. The cohort included 10,325 adult participants. The mean serum 25(OH)D level was 65.87 nmol/L, and 32.2% of patients were vitamin D deficient (<50 nmol/L). During a mean follow-up of 77 months, 1290 deaths were recorded, including 345 cardiovascular deaths and 237 cancer deaths. Patients with higher serum 25(OH)D were more likely to have lower all-cause mortality and cardiovascular mortality than those with serum 25(OH)D < 25.00 nmol/L. For cancer mortality in hypertensive patients, vitamin D may not have a predictive role in this.This study shows that higher 25(OH)D levels are significantly associated with lower all-cause mortality and cardiovascular disease (CVD) mortality. These findings suggest that maintaining adequate vitamin D status may reduce the risk of death in patients with hypertension.Copyright © 2024 The Italian Diabetes Society, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.