The present invention provides a multi-joint flexible protective device for a wire splicing sleeve to pass through a pulley. The protective device comprises a main pipe (1), movable joints (2) symmetrically installed at two sides of the main pipe; transition joints (3) connected with the movable joints (2), and a rubber sleeve passing through the transition joints (3), the movable joints (2) and the main pipe (1), the main pipe (1) and the movable joints (2) are respectively formed by two semicircular members arranged along an axis, the main pipe (1) and the movable joints (2) are movably connected, and the movable joints (2) are movably connected. The multi-joint flexible protective device for a wire splicing sleeve to pass through a pulley is reasonable in structure design, easy to install and high in intensity, is able to solve the problems that the stress of the wire at the end of the protective device concentrated and core is broken, ensure that the splicing sleeve smoothly passes through the pulley and effectively prevent the wire from being damaged, and has an important application value.