Forty-four nondiabetic patients with celiac disease (CD) were examined for the presence of insulin-dependent diabetes mellitus (IDDM)-related autoantibodies. Islet cell antibodies (ICA) were detected in 2 of 44 (4.5%). None of the 200 age- and sex-matched healthy controls was ICA positive (p < 0.05). Competitive anti-insulin antibodies (CIAA) were detected in 1 of 44 (2.5%) patients. First-phase insulin reserve (FPIR), stimulated insulin reserve (SIR), and glycosylated hemoglobin (GHB) levels were normal in the autoantibody-positive patients. Our data suggest that, like first-degree relatives of IDDM patients, CD patients are characterized by an increased prevalence of diabetes-related autoantibodies. Further follow-up is needed to determine whether the presence of these autoantibodies in nondiabetic CD patients predicts future IDDM.