Abstract: The changes of immune indexes and cytokines of patients with Graves'disease before and after treated with 131I and their correlation with thyroid function are studied in order to dicuss the pathogenesis of GD. Serum immune indexes IgG, IgA, IgM, C3, C4 and cytokines IL2, IL6, IL8 in 45 GD patients before treated with 131I, 40 GD patients of hyperthyroidism remission after treated with 131I,and 30 normal controls are measured by automatic biochemical analysis and in vitro radioassay methods. The results shows that IgG, IgM, C3, C4 and IL2, IL6, IL8 has taken part in the GD pathogenesis, the levels of IgG, IL2, IL6 had reflected the activation of GD in a way and could act as referance index to evaluate patient's condition and development of GD.