Objective: To explore the clinical application value of dual-energy imaging with Dual-source CT(2008G Siemens Somatom Definition) for head and cervical vessel diseases.Methods: The imaging data underwent dual-energy head and cervical vascular CT angiography of 146 patients suspected of head and cervical vascular diseases were analyzed retrospectively, and compared with the results of patients whole cerebral vessels DSA from February 2009 to August 2009.146 patients, male 104 cases, female 42 cases,age from 1 to 93 years old, average 53.5.Results: 77 cases with head and cervical vessel diseases were found,and remaining 69 patients with negative results, the masccline ratio 52.74%.16 patients of masccline findings underwent DSA.Only one patient was negative finding, the concordant rate 93.75%.Out of the 77 patients, 17patients were diagnosed as intracranial aneurysm, 13 with carotid artherosclerosis and stegnosis, 13 with intracranial and vertebral artery stegnosis, 9 as AVM, 7 as internal carotid artery(ICA) or Vertebral artery occlusion, 4 with neck-face AVM, 14 with others diseases.Out of the 15 patients, 8 as intracranial aneurysm, 4as ICA or Vertebral artery occlusion, 1 as carotid artherosclerosis and stegnosis, 1 as intracranial AVM and one as neck-face AVM were concordant with their DSA.Conclusion: The head and cervical vascular diseases can be demonstrated distinctly with dual energy CT, the imagings results were concordant exactly with their results of DSA.Dual energy CTA has a high diagnosis accuracy, being a practical modality for diagnosis for head and cervical vascular diseases.