Antibody drug conjugate is composed of four parts: antigen, antibody, toxin molecule, and linker, which is composed of a highly specific monoclonal antibody and a highly active small molecule toxic drug through a linker. For tumor treatment, it has the advantages of high targeting, strong specificity, and low toxicity and side effects. After the ADC drug enters the body, the antibody part binds to the target antigen on the surface of the tumor cell, and the tumor cell will endocytosize the ADC molecule, and then the ADC drug will break down in the lysosome, releasing active chemical poisons that destroy DNA or prevent tumor cells from dividing, and play a role in killing cells.