We describe 4 infants who had chronic intestinal pseudoobstruction caused by visceral myopathy. Three of the 4 were girls. Two were symptomatic at birth and 2 were symptomatic by 3 wk of age. All had abdominal distention and emaciation, 3 of the 4 had severe obstipation and fecal impactions, and 3 had signs of urologic obstruction. All had gaseous distention of the small bowel and colon, and barium studies showed dilated small bowel and colon, with slow transport through the small intestine. Two of 3 had enlarged stomachs and slowed gastric emptying, and 3 had dilated bladders and ureters. The 1 infant studied by esophageal manometry had absence of esophageal contractions. Despite total parenteral nutrition in 3, all died within 10-18 mo. The pathologic features of visceral myopathy were identified in variable sample sites from the esophagus, stomach, small intestine, colon, bladder, and ureter of the 4 infants. Of 170 family members related to 3 of the infants, there was no consanguinity and no one appeared to be clinically affected. Thus, an infantile form of visceral myopathy exists which, pathologically, is identical to the familial and sporadic forms of visceral myopathy previously identified in adolescents and adults.