We report a case of a 37-year-old woman with atypical presentation of celiac disease in relation to severe iron-deficiency and hyperthyroidism. During the investigation for iron-deficiency anemia, after exclusion of hematologic disorders, she was diagnosed with celiac disease by small-bowel biopsy. After starting the gluten free diet, the serum hemoglobin values were corrected and the symptoms of hyperthyroidism improved. Our presentation demonstrates that for patients with severe iron-deficiency anemia, the examination for the celiac disease should be considered. The quality of life and morbidity of patients with hyperthyroidism, iron-deficiency anemia and celiac disease may be improved by gluten withdrawal.