The difference between ankylosing spondylitis and rheumatoid arthritis lies in the fact that the former is a polygenic genetic disease, while the latter is an allergic disease, and there are differences in symptoms and prognosis between the two. Ankylosing spondylitis is a chronic progressive inflammatory disease of the spine, which is triggered by a combination of genetic and environmental factors, with HLA-B27 as the main susceptibility gene. Rheumatoid arthritis, one of the main manifestations of rheumatic fever, is an allergic disease closely related to group A streptococcal infection. Ankylosing spondylitis mostly occurs in the sacroiliac joints, spinal joints and other central axis joints, and is mainly characterized by low back pain and spinal ankylosis. Rheumatoid arthritis mainly manifests as wandering polyarthritis, which often involves large joints such as knee joints, ankle joints and shoulder joints. There is no cure for ankylosing spondylitis, but the symptoms can be relieved after active treatment. Rheumatoid arthritis, after active treatment, joint function can be basically restored to normal, but with recurrence. It is recommended that patients with ankylosing spondylitis or rheumatoid arthritis should consult hospitals in time and receive standardized treatment under the guidance of professional doctors.