Circulating parietal cell antibodies (PCA) were fund in 8 (5.4%) out of 147 diabetic children screened. Both sexes were equally represented, but the titres were higher in the girls. No clear relationship between the presence of these antibodies and age or the duration of diabetes was observed. Gastric studies were performed on 8 children with PCA (group A) and 41 without PCA (group B). Both basal (BAO) and maximal acid output (MAO) were significantly (p < 0.05) lower and fasting serum gastrin elevated (p < 0.01) in group A as compared with the control group. Two patients were achlorhydric. In group B, 17 patients out of the 41 studied had hyposecretion and one achlorhydria. The result became most obvious in the group with a duration and diabetes over 10 years, where MAO was significantly diminished (p < 0.05). Gastric morphology revealed atrophic gastritis in 3 patients from seven biopsies in group A and one out five biopsies for severe hyposecretion in group B. Two other children in group A had superficial gastritis. Serum ferritin levels decreased along with the duration of diabetes. Those with gastric mucosa had the lowest values.