Unilateral pulmonary artery agenesis is a rare congenital anomaly that is commonly associated with additional cardiovascular abnormalities. We report a case of intrapulmonary hemorrhage and hemoptysis in a patient with left-sided pulmonary artery agenesis as well as the first description of this anomaly in a patient with a diverticulum of Kommerell. The patient was successfully treated by performing a left pneumonectomy.