The development of pulmonary arterial hypertension (PAH) is the leading cause of mortality in patients with thalassemia and sickle cell anemia and was reported to occur in hemolytic anemias such as hereditary stomatocytosis, and paroxysmal nocturnal hemoglobinuria. Here, we report for the first time on the development of PAH in a patient with Hb-Mainz hemolytic anemia. Hb-Mainz is an unstable hemoglobin variant resulting from mutations at codon 98 of the beta chain gene (Val>Glu) characterized by severe chronic hemolytic anemia. The development of PAH in this patient further supports the contention that there is a clinical syndrome of hemolysis-associated development of PAH.