The disclosure relates to a surgical instrument and discloses a flexible drive member, an end-effector, and a surgical instrument. The flexible drive member includes a distal portion, a proximal portion, and a bendable portion therebetween, wherein the bendable portion includes a plurality of wire bundles extending in the length direction of the flexible drive member, and a flexible casing enclosing the plurality of wire bundles. In the technical solutions of the disclosure, the bendable portion is provided with some rigidity and flexibility due to the plurality of wire bundles, and the flexibly casing can fix the plurality of wire bundles relatively and can alleviate friction rate of the surface of the flexible drive member and further improve the rigidity of the flexible drive member.