Chylothorax is a relatively uncommon condition defined as an abnormal collection of lymphatic fluid within the pleural space. Morbidity of congenital chylothorax (CC) is high, and prognosis is very poor if CC is associated with hydrops fetalis. Although the optimal treatment of CC has not been determined, conservative treatment and surgical intervention are employed. However, there is still little experience with the use of octreotide therapy for this condition, and optimal duration of the treatment for response evaluation is not known. We report a newborn with CC who presented with intrauterine bilateral pleural effusion and was resistant to conservative treatments. Octreotide (6 μg/kg/h) infusion was started on the 10th postnatal day due to ongoing pleural drainage. Although the patient improved rapidly with continuous administration of octreotide, we had to continue the drug for 151 days, even subcutaneously on outpatient follow-up. To the best of our knowledge, this patient is unique in receiving octreotide treatment for such a long time, with a successful outcome and a safe profile.