Background: Pulse pressure, reflecting arterial wall stiffness, is a cardiovascular disease risk factor but is highly variable. This study investigated the association of the pulse pressure index (PPI) with 10-year cardiovascular disease risk and its clinical utility by examining its correlations with diabetes mellitus (DM) and chronic kidney disease (CKD). Methods: This cross-sectional study included 3,604 hypertensive adults (30–79 years) from the 2019–2021 Korea National Health and Nutrition Examination Survey. We categorized PPI as <30, 30 to 40, 40 to 50, and ≥50. The Framingham risk score assessed 10-year cardiovascular disease risk, and multiple regressions analyzed its relationship with the PPI category. Binary logistic regressions evaluated the relationship between PPI, DM, and CKD. Results: Adjusted for other variables, higher PPI levels are associated with an increased 10-year cardiovascular disease risk (P<0.001). PPI ≥50 was associated with CKD, and all PPI groups, except <30, were associated with DM. Conclusion: PPI predicts 10-year CVD risk and is associated with DM presence. PPI can be considered a risk factor for both cardiovascular disease and DM. Additionally, PPI ≥50 is associated with CKD.