The utility model discloses a muck discharging pipeline of a shield tunneling machine. The utility model relates to the technical field of shield tunneling machine equipment. The pipe comprises a pipewall and sealing plates, a rectangular window is formed in the lower end of the pipe wall; a circle of seam allowance with an opening facing the outer side of the pipe wall is formed in the edge of the periphery of the window, the circumferential section of the sealing plate is in an arc shape, a circle of flange is arranged on the periphery of the sealing plate, the sealing plate is connected tothe seam allowance in a clamped mode, and the flange on the sealing plate is tightly attached to the outer side of the pipe wall and is screwed and fixed through a plurality of fastening screws. A circle of sealing gasket is arranged between the sealing plate and the bottom face of the spigot, a plurality of screwed plugs are arranged on a bus at the lowest position of the sealing plate, the screwed plugs are connected to the sealing plate in a sealed mode, and the front end faces of the screwed plugs are flush with the inner wall of the sealing plate. The bottom of the pipeline is of a detachable structure, maintenance is convenient, meanwhile, the abrasion detection device is arranged, the abrasion condition can be detected in time, and maintenance can be conducted more conveniently andtimely.