The invention discloses an improvement method for a shaftless screw conveyor in the field of screw conveyors. The improvement method includes: determining the diameter of the inner wall of a screw conveyor barrel; determining screw pitch; changing section shaft of a screw; additionally paving a wear-resistant surfacing layer on the outer surface of the screw; adding a wear-resistant grille to the inner wall of the barrel located in the front within 2mm; strictly controlling gap distance between the wear-resistant grille layer on the inner wall of the barrel and the wear-resistant surfacing layer on the screw; increasing rated torque of the screw conveyor; adding grouting heads on a shell of the screw conveyor barrel; adding observation holes on the barrel. The improvement method has the advantages that the improved shaftless screw conveyor can discharge irregular thick bar reinforcements and large-sized broken concrete smoothly, self damage of the screw conveyor can be reduced, and coping capacity in case that the screw conveyor is stuck by the bar reinforcements is realized.