Ｏｂｊｅｃｔｉｖｅ　To utilize ultrasound as an approach to determine spatial distances between the right internal jugular vein and carotid artery at anterior, middle and posterior puncture sites when the neck turned to the left at various angles.　Methods　One hundred and twenty patients, classified as ASA Ⅰ or Ⅱ, were enrolled in this study. All subjects lay in supine and with a 5 cm thick pads under the shoulder. Ultrasound was used to determine the diameters of the right internal jugular vein and carotid artery, the proportions of right internal jugular vein spatially overlapping carotid artery, and the distances between the middle of right internal jugular vein and carotid artery(arteriovenous midpoint distance), at anterior, middle and posterior puncture sites when patient's neck turned to the left at angles of 0°, 15°, 30°, 45° and 60°.　Results　The diameters of the right internal jugular vein and carotid artery, proportions of right internal jugular veins non-overlapping with carotid arteries, and arteriovenous midpoint distance did not vary with puncture sites and turning angles. But at the same turning angles, percentages of right internal jugular veins non-overlapping with carotid arteries at the posterior puncture site were less than those at the anterior and middle puncture sites(P<0.05). At the anterior and middle puncture sites, percentages of right internal jugular vein non-overlapping with carotid arteries, and arteriovenous midpoint distances were similar at the turning angles of 0°, 15°, and 30°. But when the turning angles reached 45° and 60°, the percentages of right internal jugular vein non-overlapping with carotid arteries and arteriovenous midpoint distance were significantly decreased(P<0.05).　Conclusions　The spatial distances between the right internal jugular vein and carotid arteries reduced when the turning angles of the neck exceeded 45°, and at the posterior puncture site. To avoid the risk of puncturing carotid artery, operators should choose anterior or middle puncture sites and restrain the turning angle of the neck within 45°.