OBJECTIVE To examine the prevalence and predictive factors for celiac disease (CD) after a diagnosis of type 1 diabetes (T1D) in children and adolescents, to improve the current screening guidelines. RESEARCH DESIGN AND METHODS The association between sex, age at T1D diagnosis, HLA, and diabetes autoanti-bodies, and a diagnosis of CD was examined in 5,295 children with T1D from the Better Diabetes Diagnosis study in Sweden. RESULTS The prevalence of biopsy-proven CD was 9.8%, of which 58.2% already had a CD diagnosis before or at T1D onset. Almost all, 95.9%, were diagnosed with CD within 5 years after the T1D diagnosis. Younger age at the T1D diagnosis and being homozygote for DQ2 increased the risk of CD after T1D, but neither sex nor diabetes-related autoantibodies were associated with the risk. CONCLUSIONS Age at and time after diabetes diagnosis should be considered in screening guidelines for CD in children with T1D.