Aneurysm of the pulmonary artery is a rare condition in animals, and to our knowledge it has never been reported in association with pulmonary neoplasia. This report describes a case of an adult female sheep of the “Churra Galega Bragançana” breed with an aneurysm of the pulmonary artery associated with lung cancer (ovine pulmonary adenocarcinoma).Aneurysm of the pulmonary artery is a rare condition in animals, and to our knowledge it has never been reported in association with pulmonary neoplasia. This report describes a case of an adult female sheep of the “Churra Galega Bragançana” breed with an aneurysm of the pulmonary artery associated with lung cancer (ovine pulmonary adenocarcinoma).