Recombinant Anti-FGFR1 x Anti-KLB 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-FGFR1 antibody variable domain is fused to the C terminal of an IgG of anti-KLB antibody, or vice versa. The format retains desired characteristics of intact antibodies. This BsAb can bind two factors simultaneously and act as mimetic hormone (FGF21) . It is designed for the research of Type 2 diabetes therapy.