In recent decades, with the promotion of standardized treatment of rheumatic diseases and the widespread use of anti-rheumatic drugs that improve the condition, the control of rheumatic immune diseases has been greatly improved. However, there are still some patients with severe disease who do not respond well to common anti-rheumatic drugs. At this time, biological agents are a better choice. Biologics are one of the biggest advances in the field of rheumatology and immunology in the last decade or so, and are now widely used in the treatment of rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis and systemic lupus erythematosus. If ordinary anti-rheumatic drugs are like machine guns that shoot at some disordered immune responses to control the disease, biological agents are like missiles that point at an important link in the pathogenesis of the disease. For example, tumor necrosis factor alpha (TNFα) is one of the most important pro-inflammatory cytokines in rheumatoid arthritis, which can directly lead to synovial inflammation and erosion of joint bone tissue. Currently, there are many biologic agents for the treatment of rheumatoid immune diseases, targeting a wide range of targets. Comparing biologics to missiles, besides targeting the pathogenic link, they have two similar characteristics: 1. they are highly lethal; 2. they are expensive. Therefore, it is important to be careful before choosing these missiles, not everyone is suitable for their application. Patients should strictly grasp the indications and contraindications for drug use under the guidance of a physician. Generally speaking, when the following conditions are met: 1) highly active disease; 2) with poor prognostic features (including old age, female, smoking, polyarticular swelling and pain, high titers of autoantibodies, and some other specific imaging and genetic features); 3) ineffective treatment with other anti-rheumatic drugs; biologics can be considered. Certain patients with severe disease can consider the direct use of biological agents in combination with common anti-rheumatic drugs. Because biologics suppress certain immune responses in the body, they should not be used when the patient is in a state of active infection, has a tumor, or is pregnant or breastfeeding. Common adverse reactions to biologics are local reactions at the injection site and infections. Given the high incidence of hepatitis B and tuberculosis in China, particular attention should be paid to the need for screening for hepatitis B and tuberculosis related to the drug before administration. Regular and regular follow-up at the hospital is required during use. In conclusion, biological agents are like missiles, targeting the important aspects of pathogenesis, with high lethality, providing new weapons for better control of rheumatic diseases, but they also have certain side effects and should be applied under the guidance of a specialist.