The association of renal disease and autoimmune thyroid disorders has been reported previously. Renal findings associated with autoimmune thyroiditis present more commonly as proteinuria ranging from mild to nephrotic levels. We report here two adolescent girls with hyperthyroidism associated with transient proteinuria correlated with thyroid hormone levels. They had positive antithyroid peroxidase and antithyroglobulin antibodies. Ultrasonographic and scintigraphic findings of the thyroid gland were consistent with Graves' disease in both. Their renal functions were normal except proteinuria (daily protein excretion of 13.5 mg/m2/h in patient 1 and 11 mg/m2/h in patient 2). When they became euthyroid on antithyroid treatment, proteinuria decreased without associated hematuria and/or hypertension. In conclusion, patients with autoimmune thyroid disease should be assessed for the possibility of proteinuria and the etiological investigation of proteinuria should include evaluation of thyroid functions.