A 74-year-old female with lung cancer underwent thoracoscopic right upper lobectomy. The patient was diagnosed chylothorax due to the milky drain effusion on postoperative day 1 (POD 1). Despite fasting management, chylothorax was not improved. Lymphangiography by inguinal lymph node puncture was performed on POD 4. The amount of drainage decreased on POD 6 and disappered by following pleurodesis. Early lymphangiography is recommended prior to surgical treatment for patients with chyle leakages who are unlikely to be cured by conservative treatment alone.