Background: Ultrasonography (US) has been widely applied and has validated efficacy in the diagnosis of colonic polyps in children. However, little attention has been paid to improving the detection rate of polyps, optimizing the ultrasonic examination process and reducing misdiagnosis. Objective: To investigate the diagnostic performance of the colonic segment-approach by US in the diagnosis of colonic polyps in pediatric patients. Materials and methods: One hundred fifty-nine patients who were going to have a colonoscopy from September 2014 to August 2016 were enrolled in this study. All patients received US before colonoscopy. In a preliminary study, 50 patients were chosen to determine the interobserver agreement, with half of the cases with and half of the cases without a colonic segment-approach. The other 109 patients were examined by both approaches. The sensitivity and the specificity of each approach were compared based on the outcome of colonoscopy as the gold criteria. Results: The interobserver agreement was high (0.816 for the non-segmental approach, 0.754 for the colonic segment-approach). The diagnostic sensitivity of the colonic segment-approach was higher than that of the traditional approach (82.1% vs. 57.7%, P<0.05) with 89.3% vs. 64.2% detection rate of colonic polyps in the descending colon, 81.8% vs. 60.6% in the sigmoid colon, and 81.3% vs. 43.8% in the rectum, respectively. The specificity of both methods was 100% (95% confidence interval: 86.3%-100%). Conclusion: The US colonic segment-approach can improve diagnostic sensitivity for colonic polyps as a convenient method with no special requirement for equipment and examination conditions. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.