The present invention relates to the pharmaceutical field, specifically to a series of polypeptides presenting high integrin affinity and bonding capacity； three polypeptides among said series can be adopted in prevention and treatment of rheumatoid arthritis. Said three polypeptides are: polypeptide I: Ala-Cys-Asp-Cys-Arg-Gly-Asp-Cys-Phe-Cys-Gly-Gly-Gly-Gly-Ile-Val-Arg-Arg-Ala-Asp-Arg-Ala-Ala-Val-Pro (two pairs of disulfide bonds contained in the sequence are pairing in the pattern of 1-4 and 2-3)； Polypeptide II: Ile-Val-Arg-Arg-Ala-Asp-Arg-Ala-Ala-Val-Pro-Gly-Gly-Gly-Gly-Arg- Gly-Asp； and polypeptide III: mPEG-SC 20k -Ile-Val-Arg-Arg-Ala-Asp-Arg-Ala-Ala-Val-Pro-Gly-Gly-Gly-Gly-Arg-Gly-Asp. These polypeptides can be adopted in treatment of rheumatoid arthritis.
