A conical self-positioning limit feeding device and method. The conical self-positioning limit feeding device has bearing pot, empty circle in the center of bearing pot, U-shaped slide way formed between outer circle and inner circle, rotating evacuation cone and limit feeding rod arranged in the bearing pot and rotate in the same direction, and the speed of the rotating evacuation cone is greater than that of the limit feeding rod; materials are placed in the bearing pot, the evacuation cone rotates, and the materials rotate in the U-shaped slide way of the bearing pot by the torque generated by the friction between rotating evacuation cone and materials, till the long axes of the materials are tangent to the radius of the rotating evacuation cone; the limit feeding rod rotates and pushes materials to exit at equal intervals, thereby achieving the arrangement of the materials in the direction of long axis.