Recombinant Anti-CEA x Anti-TNFα Bispecific Antibody (F(ab')2-scFv2) is designed to be expressed as two chains combined via a hinge region. The scFv of the anti-CEA specificity is fused to the C terminus of the anti-TNFα Fab fragment, or vice versa. This format comprises four binding sites (two same scFv regions and two same Fab fragments), two for each antigen. This BsAb can retarget cytokine (TNFα) to tumor cells. It is designed for the research of Breast cancer; Ovary cancer; Colon cancer; Lung cancer therapy.