Objective:To investigate the feasibility of ultrasound-guided distal radial artery catheterization in children. Methods:This is a randomized controlled, non-inferiority study.A total of 250 children who underwent surgical operations and required arterial catheterization in Beijing Children's Hospital of Capital Medical University from March 2023 to July 2023 were selected.According to random number table method, the children were divided into radial artery puncture catheterization group (group R) and distal radial artery puncture catheterization group (group F), 125 cases in each group.In both groups, linear array probe was used and short axis external plane catheterization was performed under real-time guidance.The main index was the success rate of the first puncture, and the non-inferiority threshold was set at 15%.The first puncture success rate, catheterization time, artery diameter, artery depth, intraoperative and postoperative adverse reactions were recorded in the two groups. Results:The first puncture success rate of group F was not inferior to that of group R (86% vs. 84%, power difference between the two components was -2.4%, 95%CI was -11.2%-6.4%, and -11.2% was greater than the non-inferiority threshold value of -15%, P=0.0025). Compared with R group，there was no significant difference in puncture time, intraoperative and postoperative complications in group F (P 0.05). Compared with R group, the artery diameter in F group was smaller and the position was deeper, and the difference was statistically significant (P 0.05). Conclusion:Ultrasound-guided distal radial artery catheterization was not inferior to that of traditional radial artery catheterization and the puncture time was comparable, so it can be safely applied to children anesthesia as a supplementary selection site.