A method for manufacturing a torque sensor shaft by forming a magnetostrictive region including a metallic glass coating in a predetermined pattern on a side face of hollow or solid shaft-shaped workpieces, comprising the steps of rotatably attaching the shaft-shaped workpieces on a conveying pallet, successively conveying the conveying pallet to each of work devices (10, 20, 30, 40, 60, 70, 80) including a preheating device for the shaft-shaped workpiece, a thermal spraying device configured to form a metallic glass coating on a side face of the shaft-shaped workpiece, a masking device configured to provide a covering corresponding to the pattern on the coating, and a shot blasting device configured to provide shot blasting directed toward the metallic glass coating including the covering, wherein the preheating, thermal spraying, masking, and shot blasting steps are performed on the shaft-shaped workpieces while rotating the shaft-shaped workpieces on the conveying pallet at each of the work devices (10, 20, 30, 40, 60, 70, 80), each of the work devices (10, 20, 30, 40, 60, 70, 80) is provided with a conveying device configured to convey the conveying pallet along a fixed path and stop the conveying pallet at a fixed position, the conveying device is provided with a motor for rotating the shaft-shaped workpieces on the conveying pallet that has been stopped at a fixed position and a drive-side magnetic coupling for transmitting the driving force of the motor to the conveying pallet, and the conveying pallet is provided with a driven-side magnetic coupling that receives the driving force in a contactless manner from the drive-side magnetic coupling when the conveying pallet has been stopped at a fixed position, and a transmission mechanism for transmitting the driving force to each of the shaft-shaped workpieces. rotatably attaching the shaft-shaped workpieces on a conveying pallet, successively conveying the conveying pallet to each of work devices (10, 20, 30, 40, 60, 70, 80) including a preheating device for the shaft-shaped workpiece, a thermal spraying device configured to form a metallic glass coating on a side face of the shaft-shaped workpiece, a masking device configured to provide a covering corresponding to the pattern on the coating, and a shot blasting device configured to provide shot blasting directed toward the metallic glass coating including the covering, wherein the preheating, thermal spraying, masking, and shot blasting steps are performed on the shaft-shaped workpieces while rotating the shaft-shaped workpieces on the conveying pallet at each of the work devices (10, 20, 30, 40, 60, 70, 80), each of the work devices (10, 20, 30, 40, 60, 70, 80) is provided with a conveying device configured to convey the conveying pallet along a fixed path and stop the conveying pallet at a fixed position, the conveying device is provided with a motor for rotating the shaft-shaped workpieces on the conveying pallet that has been stopped at a fixed position and a drive-side magnetic coupling for transmitting the driving force of the motor to the conveying pallet, and the conveying pallet is provided with a driven-side magnetic coupling that receives the driving force in a contactless manner from the drive-side magnetic coupling when the conveying pallet has been stopped at a fixed position, and a transmission mechanism for transmitting the driving force to each of the shaft-shaped workpieces.