To positively, easily and collectively make the height of each of a number of bumps formed on a work uniform at all times, irrespective of the arrangement and the number of bumps.

A bump levelling device 10 is provided with a stage consisting of a set plate 13 and a die plate 12 for horizontally placing a wafer 14 as a work having many bumps 26 with its bump forming surface up, a levelling plate 17, a driving means 21 for vertically driving the levelling plate with its flat bottom surface put horizontally, and a spacer 15 disposed around the work placed on the stage and consisting of a thin metal plate having a predetermined thickness. The driving means 21 lifts down the levelling plate until its bottom surface abuts on the top surface of the spacer, all the bumps of the work are collectively pressed, and the height of each of the bumps is corrected into a uniform state and the top portion of each of the bumps is worked into flat.