We report a neonate with a duodenal web demonstrating the windsock appearance on US. In neonates, duodenal web is rare and its windsock appearance is also rarely seen. The windsock sign of duodenal web has been a well-known finding on upper gastrointestinal series. The corresponding windsock appearance may be demonstrated on US. Duodenal web can, therefore, be accurately diagnosed by identifying the sonographic windsock sign even in neonates.