Recombinant Anti-TG x Anti-TPO Bispecific Antibody (scFv-Fc-scFv) is designed to be expressed as one chain, then assembled to a homodimer of bivalent scFv fragments and the Fc region of IgG. The anti-TG scFv is fused to the N-terminus of Fc via a hinge region while another anti-TPO scFv is linked to the C-terminus of Fc. This scFv-Fc-scFv format has 2+2 antigen-binding valency by employing different scFv fragments. 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.