Recombinant Anti-TG x Anti-TPO Bispecific Antibody (IgG-Fv) is formed by an Immunoglobulin G (IgG) and a fragment variable Fv region, in which the Fc of IgG is engineered by KIH. The Fv region of an anti-TG antibody variable domain is fused to the C terminal of an IgG of anti-TPO antibody, or vice versa. The format retains desired characteristics of intact antibodies. This BsAb can bind two antigens simultaneously and block the synthesis of thyroid hormones. It is designed for the research of Autoimmune thyroid disease therapy.