Pulmonary arteriovenous fistula is usually considered as a subset of congenital anomalies or acquired causes which can produce a variety of conditions such as dyspnea, cyanosis, and pulmonary vascular bruit. The diagnostic methods can be diverse such as arterial blood gas analysis (ABGA), chest X-ray, chest CT and pulmonary angiogram but the most accurate diagnostic modality is thought to be the pulmonary angiogram. The complications of this disease are a rupture that can cause hemothorax, brain abscess, and cardiovascular accident, and the treatment options are either segmental resection or therapeutic embolization. A twenty-six year old female developed sudden dyspnea and visited our emergency room. The patient was diagnosed as having pulmonary arteriovenous fistula (size; 4${ imes}$4${ imes}$3 cm) in the superior segment of the right lower lobe, evidenced by chest CT and pulmonary angiogram. Consequently, she underwent an emergency right lower lobectomy. We report this rare case of combined hemothorax that we have experienced, from diagnosis to treatment.