The invention provides a vibration-absorption designing method of a damping structure of a blisk. The method comprises steps as follows: the mounting position range of a damper is selected according to a blisk model; the range of exciting force is determined, and a vibration amplitude monitoring point is selected; a contact surface and the positive pressure range are determined; vibration amplitudes of the monitoring point are calculated as exciting force, positive pressure and damper mounting positions vary; optimal dimensionless positive pressure is determined, and dimensionless positive pressure is the ratio of positive pressure to exciting force; the optimal mounting position and the optimal quality of the damper are determined according to the optimal dimensionless positive pressure.