A high prevalence of parietal cell antibodies (PCA) has been reported in children with autoimmune thyroid disease (AITD). The aim of this study was to determine the prevalence of autoimmune gastritis markers among children diagnosed as AITD.We studied 26 patients with AITD. Basal samples were taken to determine: hemogram, vitamin B12 and folic acid plasmatic levels, gastrin plasmatic levels, and PCA's determination. Other autoimmune disease comorbidity were also studied.Free T4 and TSH values were normal, with hormonal substitutive treatment. Hb, MCV, HCM, vitamin B12, folic acid and gastrin were in normal range for all 26 patients. We reported 6 cases diabetes mellitus type 1 and 2 of celiac disease. A single patient was PCA positive. It was a 14-year-old hyperthyroid girl without any other autoimmune disease.AITD in childhood and adolescence is associated with other autoimmune diseases, specially DM1 and CD. PCA becomes an early and sensitive marker to detect autoimmune gastritis.