Recombinant Anti-TG x Anti-TPO Bispecific Antibody (Fab-scFv-Fc) requires expression of three polypeptide chains, encoding two heavy chains (Fc-containing chains) and one light chain, respectively. The Fab of anti-TG antibody variable domain is fused to the Fc-knob domain with a hinge region and the same as the scFv of anti-TPO to the Fc-hole domain, or vice versa. The Fab-Fc and scFv-Fc fragments can be paired via the interaction of the Fc regions. 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.