The invention discloses a Bingham fluid valve-element-free overflow device and method. The device comprises a cushion cylinder, cylindrical pins, steel pipes, a liquid collecting cylinder, a base and bolts. The cushion cylinder is composed of a cylindrical cushion cylinder cover and a cylindrical cushion cylinder body in a welded mode. Six sets of liquid outlets are formed in one side of the cushion cylinder body, and one ends of the steel pipes are connected with internal threads of the liquid outlets through external threads. Pin holes are formed in the circumferential surface of the cylinder of the cushion cylinder body, and the cylindrical pins are installed in the pin holes in a matched mode. Hexagon nuts are arranged at the outer ends of the cylindrical pins. Through holes are formed in the inner ends of the cylindrical pins. The liquid collecting cylinder is composed of a cylindrical liquid collecting cylinder body and a cylindrical liquid collecting cylinder cover in a welded mode. The side face of the liquid collecting cylinder body is provided with round unthreaded holes which are right opposite to the liquid outlets. The other ends of the steel pipes are directly overlapped into the round unthreaded holes. When the through holes in the cylindrical pins are collinear to the liquid outlets, liquid in the cushion cylinder can enter the steel pipes, and the on-way resistance of Bingham fluid in the steel pipes serves as the overflow pressure of the device.