The probability of occurrence in double bubble sign is about 1 in 10,000 infants. The double bubble sign refers to the visualization of two vacuole-like structures in the abdomen on imaging, usually in parallel and without echoes, and is seen in about 1 in 10,000 infants; some fetuses may also be visualized on ultrasound during pregnancy testing, which is usually suggestive of congenital duodenal pathology. The double bubble sign is characteristic of duodenal obstruction, which can occur in congenital duodenal atresia, duodenal stenosis, intestinal torsion, etc. It is helpful in determining the severity and cause of obstruction. Once the double bubble sign is found in the clinic, it is necessary to go to the hospital for timely consultation, and if necessary, surgical treatment is needed to avoid serious consequences.