Postoperative chylothorax is a serious complication increasing rates of both mortality and morbidity in patients who undergo thoracic surgery. A total of 41 patients with the diagnosis of postoperative chylothorax were divided into four groups considering the initial amount of chylous drainage per day: Group A (n=25, <200 mL), Group B (n=9, 200-500 mL),Group C (n=6, 500-1000 mL) and Group D (n=1, >1000 mL). All of the patient groups were examined in terms of duration of chylous drainage, treatment method, type of correction surgery and length of hospital stay. Conservative treatment was adequate for the patients in Group A and B, whereas we performed 2 thoracoscopies and 4 thoracotomies for Group C and one thoracotomy for the patient in Group D. Re-surgery via thoracotomy included thoracic duct ligation for 3 and mass ligation for 2 patients, whereas thoracoscopic correction was achieved by mass ligation for the remaining two cases. As a conclusion, we suggest that surgery shall be considered for the patients with deterioration in status or for whom developing drain output of 500 to 1000 mL for at most 8 days or more than 1000 mL in 24 hours after the initial operation.