PROBLEM TO BE SOLVED: To provide a new pharmaceutical composition for prevention or treatment of cancer that inhibits the action of c-Met, a tyrosine kinase receptor.SOLUTION: Disclosed are an antibody or antigen binding fragment thereof that specifically binds to an epitope in a SEMA domain of c-Met, and pharmaceutical compositions, methods, kits, nucleic acids, and cells related thereto. Also disclosed is an antibody or antigen binding fragment thereof that is an antagonist of c-Met protein.SELECTED DRAWING: Figure 4【課題】チロシンキナーゼ受容体であるc-Metの作用を阻害する、がん予防用またはがん治療用の新たな医薬組成物の提供。【解決手段】c-MetのSEMAドメイン内のエピトープに特異的に結合する抗体またはその抗原結合断片、並びにそれと係わる医薬組成物、方法、キット及び細胞。c-Met蛋白質の拮抗剤である、抗体又はその抗原結合断片。【選択図】図4