Neonatal pyloric obstruction is characterized by vomiting, oliguria, malnutrition, jaundice, gastric peristaltic waves and right upper abdominal mass. 1. Vomiting: usually occurs 2~4 weeks after birth. At first, it is milk spillage, and then gradually aggravates to show projectile vomiting. The vomit does not contain bile. In a few cases, the frequent vomiting causes the capillaries of the gastric mucosa to rupture and bleed, so the vomit may contain blood or coffee-like material. 2. Oliguria: When frequent vomiting occurs, a large amount of water and food is vomited out, resulting in oliguria and decreased frequency of bowel movements. 3. Malnutrition: Due to repeated vomiting, insufficient intake of nutrients and water, and large loss of hydrogen ions and chloride ions, children gradually become malnourished and dehydrated. 4. Jaundice: a few children with jaundice, which can disappear a few days after surgery. 5. Gastric peristaltic wave: the upper abdomen is bulging, the lower abdomen is flat and soft. Gastric peristaltic wave is common, and it disappears after moving from the left subcostal area to the right upper abdomen. 6. Right epigastric mass: a hard, olive-shaped, movable mass can be detected in the right epigastric region. Newborns with the above symptoms should go to the hospital in a timely manner, under the guidance of the doctor standardized treatment.