Until recently, assessment of patients with pulmonary hypertension has mainly relied on functional and haemodynamic parameters. Health-related quality of life (HRQOL), however, has become increasingly important in defining overall health status. The present study investigated the performance and clinical relevance of the Minnesota Living with Heart Failure (MLHF) questionnaire by prospectively studying 48 patients with either pulmonary arterial hypertension (n = 26) or chronic thromboembolic pulmonary hypertension (n = 22). The MLHF scores were correlated to various clinical and haemodynamic parameters. Prognostic outcome was evaluated by calculating the time taken to reach an adverse clinical event defined as death, lung transplantation or pulmonary endarterectomy. The reliability of test-re-test and internal consistency of this HRQOL tool was high. The MLHF score and its physical subscore correlated moderately to well with functional and haemodynamic parameters, except in the case of pulmonary artery pressures. Both scores significantly improved during vasodilator therapy. This figure was surpassed only by the New York Heart Association/World Health Organization functional class. A multivariate analysis of all variables revealed that the MLHF score was the sole factor predicting subsequent outcome. The Minnesota Living with Heart Failure questionnaire is highly reproducible, consistent, and a moderately valid and responsive tool in assessing health-related quality of life in pulmonary hypertension. Moreover, it is a significant predictor of outcome in these patients.