Purpose: Adenovirus infection with swollen Peyer patches in the ileum, known as one of the causes of intussusception, may cause vitamin C depletion in human body because vitamin C is a first line antioxidant. Or low vitamin C status in human body makes the man more susceptible to infection of adenovirus in the ileum with a markedly swollen lymph node. In this study, we tried to find out the relationship between pediatric intussusceptions and vitamin C concentrations of whole blood and plasma. Methods: Whole blood and plasma vitamin C concentrations of fifty-seven patients with intussusceptions from May 1995 to December 1998 at the Gyeongsang National University Hospital were compared with those of 256 normal healthy children. Vitamin C was measured by the 2, 4-dinitrophenylhydrazine methods. Results: The average age of patients (male=39, female=18) with intussusceptions was fifteen months of age. Whole blood vitamin C concentrations of patients and healthy children were $1.49{pm}0.64$ mg/dL, and $2.18{pm}0.49$ mg/dL, respectively. Plasma vitamin C concentrations of patients and healthy children were $0.59{pm}0.36$ mg/dL, $1.47{pm}0.56$ mg/dL, respectively. But no differences in the vitamin C concentrations of whole blood and plasma according to age, degree of leukocytosis, fever, interval from onset, hematochezia, and need for operation were found. Conclusion: Whole blood and plasma vitamin C concentrations of patients with intussusceptions were lower than those of healthy children (P=0.0001). Prospective studies are needed to elucidate whether these results were consequences or causes of intussusceptions.