The invention relates to a falling beam construction beam end sliding auxiliary device and a use method. The height of the device is greater than the height of a beam end support. The device comprisescushioning stones which can be fixed on two sides of a bridge abutment upper beam end support, wherein a heating element is embedded into each cushioning stone and can heat the cushioning stone to ahot melting state, the top surface of each cushioning stone is fixedly provided with a supporting element, the top surface of the supporting element is provided with a groove in which a plurality of rolling shafts are arranged, and the rolling shafts can roll in a longitudinal direction of a bridge in the groove, wherein the diameter of each rolling shaft is greater than the depth of the groove. By use of the sliding auxiliary device, the damage of the beam end support by a steel box beam during falling beam construction can be effectively avoided.