Pulmonary lymphangiomatosis is a rare disorder involving the entire intrathoracic lymphatic system from the mediastinum to the pleura. Pulmonary lymphangiomatosis mostly occurs in children and young adults without gender predilection. Although it is pathologically benign, it shows a progressive and fatal course with variable initial presentation. We now report a case of pulmonary lymphangiomatosis in a 35-year-old man. He presented with hemoptysis 6 months previously. Chest x-ray and a chest computed tomography scan showed diffuse interstitial thickening with left pleural effusion. Chylothorax was confirmed by thoracentesis. Lymphangiography showed dilated and tortuous lymphatic channels. Surgical lung biopsy revealed proliferation of complex anastomosing lymphatic channels. He was diagnosed with pulmonary lymophangiomatosis. Closed thoracostomy and chemical pleurodesis were done and the dyspnea was reduced.