To investigate the possible relationship between enteric adenovirus types 40 and 41 and intestinal intussusception in children.Prospective, case-control patient study.Sixty-three consecutive children suspected clinically of having intestinal intussusception were enrolled in this study. Of these, 25 children (mean age, 1.4 years; range, 3 months to 5 years) had barium enema examination-proved intussusception. Age-matched normal controls (24) and controls with diarrhea (21) were obtained within 1 month of the index case.Stools were tested for the presence of nonenteric adenovirus and enteric adenovirus using a monoclonal antibody-based enzyme immunoassay. Five (20%) of 25 children with intussusception had nonenteric adenovirus in their stools compared with one (4%) of 24 normal controls, none (0%) of 21 of the controls with diarrhea, and none (0%) of 37 patients suspected of having intussusception who had negative results on barium enema examination. However, no stool samples were positive for enteric adenovirus.Nonenteric adenovirus infection and intestinal intussusception may be associated. However, because enteric adenovirus was not found in any of the groups studied, no conclusions can be made regarding their possible influence on the risk for developing intussusception.