Objective <p>Evidence on the correlation between Oxidative Balance Score (OBS) and the risk of congestive heart failure (CHF) in hypertensive patients remains limited. This study aimed to explore the association between OBS and the risk of CHF in hypertensive patients.</p> Methods <p>We assessed the association between the Oxidative Balance Score (OBS) and congestive heart failure (CHF) risk in hypertensive patients using weighted, multivariable-adjusted logistic regression. The Weighted Quantile Sum (WQS) regression model quantified the relative contributions of individual components within the OBS. Nonlinear exposure-response relationships were evaluated with Restricted Cubic Spline (RCS) analysis. Model sensitivity and specificity were determined via Receiver Operating Characteristic (ROC) curves. Subgroup analyses examined heterogeneity across predefined clinical strata, and mediation analysis explored potential mechanistic pathways.</p> Results <p>A significant negative correlation was found between OBS and the risk of CHF in hypertensive patients (OR = 0.56 [0.40, 0.77], <i>p</i> &lt; .0001), and this relationship was linear (P for nonlinear &gt; 0.05, P for overall &lt; 0.001). There was an interaction between OBS components (0.377 [95% confidence interval (CI): 0.267–0.532], <i>p</i> &lt; .001). Among them, alcohol has the strongest impact on CHF risk (0.47%). The model demonstrated strong predictive performance, achieving an area under the ROC curve (AUC) of 0.725 (95% CI: 0.691–0.739). Subgroup analyses revealed no significant heterogeneity (<i>P</i> &gt; .05). Serum creatinine (Scr) potentially mediate the relationship between OBS and CHF risk (Proportion = 17.7%).</p> Conclusion <p>A significant negative correlation was found between OBS and CHF risk in hypertensive patients, with Scr potentially playing a mediating role. Alcohol consumption had the greatest impact on the risk of CHF in hypertensive patients.</p>