Patients with portal hypertension may develop pulmonary complications such as hepatopulmonary syndrome (HPS) or portopulmonary hypertension (PPHT). PPHT is defined as elevated pulmonary pressure, elevated pulmonary vascular resistance, a normal pulmonary capillary wedge pressure, and portal hypertension in the absence of other known causes pulmonary hypertension. Various factors such as hyperdynamic circulation, volume overload, and circulating vasoactive mediators are suspected to be involved in the pathogenesis of PPHT. The prognosis of patients with severe PPHT is significantly reduced due to the risk of right heart failure. In patients with moderate to severe PPHT liver transplantation is associated with a significantly increased mortality. The chief symptom of PPHT may be dyspnoe in the presence of typical histomorphological alterations comparable with idiopathic pulmonary hypertension. Continuous intravenous application of prostacyclin is currently regarded as the treatment of choice for patients with severe PPHT. Inhaled prostacyclin or its analogue iloprost or oral treatment with the endothelin-receptor antagonist bosentan may be promising alternatives which should be further investigated in randomized controlled trials.