Recombinant Anti-pre S2 protein x Anti-S protein 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-pre S2 protein antibody variable domain is fused to the C terminal of an IgG of anti-S protein antibody, or vice versa. The format retains desired characteristics of intact antibodies. This BsAb can bind two antigens simultaneously. It is designed for the research of HBV infection therapy.