Chyle leakage after modified radical neck dissection is a rare condition that could be occasionally life-threatening if untreated. We report the first case of successful management of a thoracic duct injury using Viscum album extract (Helixor-M). A 54-year-old woman diagnosed with papillary thyroid cancer of the right lobe of the thyroid with metastasis to cervical lymph node levels II-VI, bilaterally, underwent total thyroidectomy and modified radical neck dissection. Three days postoperatively, the surgical team identified a thoracic duct injury due to drainage of chyle from the Jackson-Pratt drain inserted in the right side of the patient`s neck. Various medical treatments (octreotide, withdrawal of enteral feeding, and total parenteral nutrition) and surgical treatments [lymphatic ligation of cervical lymph node level IV and negative pressure wound therapy (vacuum-assisted closure)] were performed, but the drainage persisted. Viscum album extract (Helixor-M) was then injected through the drain. The dose of Viscum album extract was increased while being cautious of its adverse effects, such as nausea, vomiting, erythema, induration at the injection site, and flu-like symptoms. The injection was effective in stopping the drainage and the patient's condition improved, without recurrence. The patient was discharged on the 64 th postoperative day without any further complications. Our results suggest that treatment of thoracic duct injury after neck surgery with Viscum album extract (Helixor-M) may be a novel, less invasive alternative approach to treat cases resistant to standard treatments.