We analyzed 72 cases of pneumatosis intestinalis at the Hospital Infantil de México during a 32 years period. We found the higehst incidence in children under 6 months of age. In the new-born period, the entity is associated with necrotizing entrocolitis and in the older children group, this alteration is associated with gastroenteritis. The diagnosis was made by radiology in 93% of the cases and in 7%, it was made at the surgical event. We propose 3 mechanisms in the pathophysiology of the entity having all of them disruption of the integrity of the intestinal mucosa and higher pressure of the intraluminal gas. The mortality rate was high because we included cases from the initiation of the hospital's activities (1943). The conclusion is: 1) The prognosis is based on an early diagnosis. 2) It is imperative to take proper care of the complication. 3) It is also very important to give a rest for variable period of time to the injured intestine with parenteral feeding and eventually, elemental feeding.