Recombinant Anti-VEGFB x Anti-VEGF Bispecific Antibody (Fab-Fv) is designed to be expressed as two polypeptide chains. The heavy chain Fd fragment and light chain of an anti-VEGFB antibody are fused with the VL and VH domains of an anti-VEGF antibody respectively. It can form natural in vivo heterodimerization. This BsAb can block two proangiogenics simultaneously. It is designed for the research of Cancers therapy.