Cysts of the thoracic duct are uncommon entities that can occur in the abdominal segment, the cisterna chyli, the thoracic segment and the cervical segment of the thoracic duct. The rarest presentation is in the cervical segment, with only seventeen cases reported in English literature. The diagnosis can be made by puncture and with the use of computed tomography or ultrasonography. The cystic fluid always contains an excess of T-lymphocytes and triglycerides. Except for two cases, all reported cervical thoracic duct cysts were surgically treated by excision and ligation of the lymphatics connected to the cyst. We present a case of a successful non-operative treatment of a cervical thoracic duct cyst that was resolved by repeated aspiration and dietary changes only.