Abstract: A kneading apparatus includes a plurality of rotatable discs mounted on a screw shaft disposed on a hollow cylinder and a plurality of fixed doughnut members mounted on an inner wall of the hollow cylinder. The rotatable discs and fixed doughnut members are arranged alternately in an extending direction of the screw shaft. Projected portions and recessed portions extending radially and alternately arranged in a circumferential direction are formed on opposing side faces of the rotatable disc and fixed doughnut members in such a manner that the depths thereof are increased in proportion to the distance from a center of the screw shaft. Accordingly, the kneading apparatus is allowed to have a small construction and yet capable of efficiently kneading the material. In addition, material is prevented from remaining locally in the apparatus, and thereby a proper shear force is applied to the entire material.