Recombinant Anti-FGFR1 x Anti-KLB Bispecific Antibody (Miniantibody) is a fusion protein of two scFv fragments combined with distinct specificity. One scFv of an anti-FGFR1 antibody variable domain is linked to another scFv of an anti-KLB antibody variable domain by a flexible hinge region. This BsAb format has the decreased size and better penetration than conventional IgGs in the clinical diagnostics and potentially therapy. This BsAb can bind two factors simultaneously and act as mimetic hormone (FGF21) . It is designed for the research of Type 2 diabetes therapy.