Thrombosis of the external jugular vein (EJV) is an infrequent clinical condition that has been associated with central venous catheterization, head and neck infections, intravenous drug abuse, and compression at the affected site. The authors report a case of thrombotic obstruction of the EJV in the late postoperative period after laparoscopic anterior lumbar interbody fusion. A 40-year-old morbidly obese woman with a depressive syndrome was diagnosed with L5-S1 discopathy and was submitted to laparoscopic anterior isthmic fusion. The operation lasted approximately 6 hours, during which the patient remained in a supine decubitus and Trendelenburg position. The left radial artery, peripheral veins, and right internal jugular vein were canalized. The internal jugular vein catheter was electively withdrawn 24 hours after the intervention. The postoperative period was satisfactory, and the patient was started on prophylaxis with low-molecular-weight heparin. She sat up and began walking at 24 hours and was discharged to her home 4 days after the procedure. Eight days after discharge she returned, experiencing right cervical pain. Palpation revealed a painful induration and erythematous area under the anterior edge of the sternocleidomastoid muscle. Results of otoscopy and laryngoscopy were normal. Cervical echo-Doppler disclosed an image consistent with EJV thrombosis. The most frequent causes of jugular vein thrombosis are mentioned above. A higher incidence has been described after upper abdomen and pelvic surgery; other contributing factors are age, obesity, and associated illness. There are few references in the literature to position-induced EJV thrombosis in the late postoperative period. The authors' patient presented signs and symptoms of EJV thrombosis (probably because of various factors), which was confirmed by echo-Doppler study and treated with 10 days of calcic heparin.