Ultrasound is an important imaging modality for evaluation of the gastrointestinal (GI) tract in children. Ultrasound is often the imaging study of choice in children presenting to the Emergency Department with vomiting, abdominal pain, and lethargy not explained by initial plain abdominal films. There is no need for preparation in the emergent setting and the lack of ionizing radiation is in accordance with the As Low As Reasonably Achievable (ALARA) principle. Ultrasound techniques for assessment of the pediatric GI tract are reviewed, followed by a discussion of normal development and anatomy. The definition, incidence, and typical clinical presentation of disorders affecting the GI tract from the esophagus to the anorectal region are provided, including infectious, inflammatory, and congenital, and neoplastic abnormalities, as well as anatomic variants that can predispose to volvulus and obstruction. A brief overview of management is also provided.