This invention relates to the pharmaceutical field, specifically to a series of integrin blockers that present strong angiogenesis inhibiting performance, high integrin affinity and integrin-bonding capacity. This series of integrin blockers can be adopted in treatment of solid tumors and rheumatoid arthritis. Specifically, said series of integrin blockers include polypeptide I, polypeptide II and polypeptide III (see Seq. No.1, Seq. No.2 and Seq. No. 3) that can be adopted in treatment of solid tumors and rheumatoid arthritis. This invention also relates to application of these three integrin-blocking polypeptides in preparation of anti-tumor drugs, wherein the tumors that can be treated include those primary or secondary cancers originated from head and neck region or other organs such as brain, thyroid, esophagus, pancreas, lung, liver, stomach, breast, kidney, gallbladder, colon, rectum, ovary, cervix, uterus, prostate, bladder and testicle, as well as melanoma and sarcomas.
