Recombinant Anti-CA125 x Anti-HER2 Bispecific Antibody (scDiabody-Fc) is a fusion protein of two scDiabodies with an Fc region. In single-chain Diabodies, an additional connecting linker is introduced between chains of the anti-CA125/anti-HER2 diabody. The scDiabody with two specificities is further fused to the Fc domain to form BsAb with 2+2 antigen-binding valency. This BsAb can bind two factors simultaneously. It is designed for the research of Breast cancer; Gastric cancer; Prostate cacncer; Ovarian cancer; Solid tumors therapy.