Aerophagia is a functional gastrointestinal disorder characterized by repetitive air swallowing, abdominal distension, belching and flatulence. Pathologic aerophagia is a condition caused by the swallowing of excessive volumes of air with associated various gastrointestinal symptoms, such as burping, abdominal cramps, flatulence and a reduced appetite. It is a clinical entity that can simulate pediatric gastrointestinal motility disorders, such as gastroparesis, megacolon and intestinal pseudo-obstruction, and presents more frequently in children with mental retardation. Early recognition and diagnosis of functional aerophagia or pathologic aerophagia is required to avoid unnecessary, expensive diagnostic investigations or serious clinical complications. Functional aerophagia is frequent in the adult population, but rarely discussed in the pediatric literature. We present two pediatric clinical cases with a history of functional constipation in whom gaseous abdominal distension was the most important symptom. Mechanical intestinal obstruction, chronic intestinal pseudo-obstruction, malabsorption and congenital aganglionic megacolon were ruled out. Extensive gaseous abdominal distension was due to aerophagia, and treatment consisted of parents' reassurance and psychological counseling.