The present invention is a separation device that separates a particulate highly absorbent polymer and a liquid-absorbent fiber contained in the material of an absorbent article. The present invention has: a belt member that moves along a predetermined direction while receiving the material, which is dropping down, at the upper surface thereof and an airflow supply mechanism that supplies a flow of air in the reverse direction from the direction of motion of the belt member along the upper surface from the downstream side of the direction of motion with respect to the dropping down position of the material. When the highly absorbent polymer is being sent to the downstream side in the direction of motion by means of the motion of the belt member, the flow of air forms fiber balls by rolling the liquid-absorbent fiber over the upper surface of the belt member while restricting the motion to the downstream side of the direction of motion of the liquid-absorbent fiber, thus separating the liquid-absorbent fiber and the highly absorbent polymer.
