Autoimmune disease is a kind of heterogeneous disease caused by the loss of immune tolerance to autoantigens.In recent years,antibody drug has become an important choice for the treatment of autoimmune diseases.Monoclonal antibodies are limited by their large relative molecular mass and difficult to penetrate solid tissues,while nanobodies,the smallest antibody fragment known to date with intact antigen recognition,have gained much attention in the treatment of autoimmune diseases due to their ease of modifi-cation,high penetration,and ability to target more cryptic epitopes.The review focuses on the application of nanobodies in the treat-ment of diseases such as rheumatoid arthritis,acquired thrombotic thrombocytopenic purpura,systemic lupus erythematosus,psoria-sis,and looks forward to the prospect of nanobodies in the treatment of autoimmune diseases.