The clinical significance of anti-cyclic citrullinated peptide antibody is for the early diagnosis of rheumatoid arthritis and identification of patients with rheumatoid arthritis who may develop joint bone destruction and joint deformity. This antibody is highly specific for rheumatoid arthritis and is associated with early diagnosis and prognosis of rheumatoid arthritis. Anti-cyclic citrullinated peptide antibody is highly specific for the diagnosis of rheumatoid arthritis and can be applied in the early diagnosis of rheumatoid arthritis. Its sensitivity for the diagnosis of rheumatoid arthritis can have a level of 50% to 80%, while the specificity can reach more than 90%, and the positivity rate of early-stage patients can reach 80%. In addition to early diagnosis of rheumatoid arthritis, anti-cyclic citrullinated peptide antibody can also be used to identify rheumatoid arthritis patients with joint bone destruction, joint deformation and other conditions. A positive antibody with a high titer indicates that the patient is prone to joint bone destruction and joint deformity. In addition, anti-cyclic citrullinated peptide antibodies have clinical significance in determining the activity of rheumatoid arthritis, and it is recommended that patients seek prompt medical attention and consult a physician.