Recombinant Anti-FGFR1 x Anti-KLB Bispecific Antibody (scFv-CH3) contains two chains. The anti-FGFR1 scFv is fused to the Knob-CH3 domain via a hinge region and the same as the anti-KLB scFv to the Hole-CH3 domain, or vice versa. The KIH CH3 domains can facilitate to form a heterodimer and this bivalent binding leads to improvement in avidity. This BsAb can bind two factors simultaneously and act as mimetic hormone (FGF21) . It is designed for the research of Type 2 diabetes therapy.