S U M M A R Y: Background: Malnutrition is a common yet underrecognized comorbidity in pulmonary hypertension (PH) and may adversely affect patient outcomes. This study evaluated the prognostic impact of malnutrition in PH patients. Methods: A retrospective cohort of 350 PH patients treated at a U.S. tertiary center between January 2017 and December 2023 was analyzed. Patients were stratified into four groups based on nutritional status. Survival analysis using Kaplan-Meier estimates and multivariable Cox regression identified predictors of mortality. Results: Of the 350 patients, 22.8% had severe malnutrition, which was significantly associated with lower median survival (18 vs. 36 months, P < 0.01). In adjusted models, severe malnutrition independently predicted increased mortality (HR: 2.5; 95% CI: 1.8–3.6; P < 0.01). Other predictors included age (HR: 1.03), NYHA class III-IV (HR: 1.8), elevated pulmonary arterial pressure (HR: 1.05), low serum albumin (HR: 0.6), and comorbidities (HR: 1.4). Conclusion: Severe malnutrition is a strong, independent predictor of mortality in PH patients. Routine nutritional assessment and early intervention may improve survival and clinical outcomes in this high-risk population.