Life threatening hemorrhage in patients with malignant tumours of the head and neck area are often, as a result of tumour infiltration, postoperative anatomical changes, infection and radiological necrosis, difficult to control. One option for prophylaxis and treatment is the ligature of the external (ECA) or common carotid artery (CCA) and superior thyroid artery (STA). 52 patients were examined in a retrospective study to determine both the hazards and the therapeutic use of the procedure. The external carotid artery (ECA) was ligated prophylactically during the operative procedure of tumour resection and neck dissection in 25 patients. In 27 cases closure of the ECA, CCA or ECA and STA was carried out as an emergency procedure for acute hemorrhage following completed primary treatment (operation, primary or postoperative radiation or radiochemotherapy). There was no postoperative hemorrhage after prophylactic ligature of the ECA. One patient with multiple cardiovascular diseases suffered from an ipsilateral cerebral infarction 1 year after operation. In 6 of 9 patients and in all 3 patients, in whom ligature of the CCA or ECA and STA respectively was carried out as an emergency procedure, severe neurological complications up to an apallic syndrome occurred. The number of deaths due to acute hemorrhage was considerably smaller among those patients with prophylactic ligature of the ECA performed during operative procedure of tumor resection and neck dissection. In addition there were much less unfavourable courses in the sequence of prophylactic closure of the ECA than observed after ligating the CCA or ECA and STA in an emergency situation.