Objective To explore the optimization and standardization of imaging parameters for 16-slice spiral CT angiography in intracranial and cervical arteries. Methods Sixty patients were randomly divided into three groups, and the automatic bolus tracking thresholds of 100, 150 and 180 HU in the descending aorta were used respectively. The CT values of artery and vein among three groups were compared. Other 40 patients were randomly divided into A and B group and underwent CTA with different slice thickness and pitch, and the difference in arterial display were compared. Results The carotid and intracranial arteries in all three groups were well displayed. No statistical difference was found in enhancement CT values of three points of common carotid artery and internal carotid artery among three groups (P>0.05), while the differences of CT values in same level vein among three groups were significant (P<0.05). There was no significant difference in the average score of display degree between group A and B. Conclusion Imaging parameters for 16-slice spiral CT angiography in intracranial and cervical arteries are recommended as follows:100 HU (threshold), 120 kV, 280 mA, 1.25 mm (thickness), 1.375:1 (pitch), 0.5 s/r and 16×0.625 mm (effective thickness).