Pulmonary arteriovenous malformations (PAVMs) are rare anomalies. The degree of right-to-left shunting, which can lead to cyanosis and paradoxical embolism causing neurological complications, determines the prognosis. We report two cases of PAVM and review the literature. A 45-year-old woman with clinical signs and symptoms of PAVM was examined using several different scanning techniques, which showed a large PAVM in the lower lobe of her right lung. A lobectomy was performed, which revealed a 5 cm diameter PAVM with one feeding artery and multiple veins. Intravenous angiography of a 7-year-old girl with symptoms of fatigue and acro-cyanosis confirmed the presence of a large PAVM in her right lower lobe. The PAVM had two major arteries arising from the aorta, which were ligated during a lobectomy. Both patients recovered well following surgery. Although PAVMs are rare, their neurological and haemodynamic consequences may be fatal. Interventional treatment techniques, including surgery, are usually curative.