Antibody drug plays a critical role in biotechnology pharmaceutical field. It is a long term goal for antibody to diagnose and treat disease by its specific for antigen recognition. The discovery and application of antibody are inseparable from immunology. From the immune system, a detailed description of the historical process of discovery and clinical application of antibody was carried out. In recent years, cell engineering and genetic engineering technology as the main antibody engineering technology have been a hot field of pharmaceutical biotechnology. Antibody drug development and industrialization are entering a new age rapidly.