ABSTRACT Objective To evaluate the consistency and accuracy of embracing and supine ultrasound and inverted X-ray in the diagnosis of congenital anorectal malformation (CARM) before operation.Methods There were 122 cases of congenital anorectal malformation were clinically diagnosed divided into low group and middle-high group. The distance from the distal rectal pouch to the perineum ( P-Pe) was measured by embracing position ultrasound, supine ultrasound, and inverted X-ray before operation. Compared the consistencyand analyze the accuracy of the three methods for P-Pe measurement.Results The sensitivity of embracing position ultrasound, supine ultrasound, and inverted X-ray preoperative application were respectively 97.18 %, 91.54 % and 77.64 %. The specificity of three methods were respectively 96.08 %, 96.08 % and 98.04 %. The coincidence rates were respectively 96.72 %, 93.44 % and 86.07 %. Kappa index was respectively 0.933, 0.867 and 0.725. The area under the ROC curve of embracing position ultrasound, supine ultrasound, and inverted X-ray were respectively 0.992, 0.987 and 0.972, and there was a significant difference (P < 0.001 ). The inverted X-ray measurement results of the middle-high position group were higher than that of the operation measurement ( P < 0.05 ). There was no significant difference between the measurement results of embracing position ultrasound and supine ultrasound compared the operation measurement ( P > 0.05 ). By using completely randomized design data variance analysis, the lower-level group have different means of measurement for different methods (F=46.356, P＜0.001). By using the Dunnett test of pairwise comparison between the means of multiple samples, the supine position ultrasound and the inverted position X-ray measurement results were higher than the surgical measurement values in the lower-level position group ( P<0.05), and there was no statistically significant difference between the embracing position ultrasound and the surgical measurement (P>0.05).Conclusion The accuracy and consistency of the three methods for diagnosing CARM are all higher in the middle-high group. But in the lower-level position group, the ultrasound diagnosis is superior to the inverted X-ray. So, embracing position ultrasound for P-Pe distance measurement has more accurate and clinical value and provides a strong basis for the selection of surgical methods.