Abstract: Objective:To explore the application value of 80kV tube voltage combined with iterative reconstruction technology in CT angiography of lower extremity artery. Methods:40 patients were randomly divided into two groups. The parameters of scanning and injection were 80kV in the experimental group and 100kV in the control group. The radiation dose, contrast dose and image quality were compared between the two groups. Results:The effective radiation dose and contrast dose (95mL) of the control group were significantly higher than those of the experimental group, the difference was statistically significant (P<0.001); there was no statistical difference between the two groups in the CT value of vascular enhancement and the subjective score of image quality (P>0.05). Conclusion:The CT scanning technology of 80kV tube voltage combined with iterative reconstruction technology can significantly reduce the radiation dose and contrast agent dose on the premise of ensuring the image quality, which has important application and promotion value.