Abstract: Provided is a method for mounting a device on a frame in a construction machine. The method includes forming plate holes in a beam member at respective mount-member-provision positions on the beam member; mounting a plate supporter on a back surface of the beam member at each of the mount-member-provision positions so as to border the plate hole at a lower side thereof; installing the beam member on the frame; putting the mount plate into the plate hole from above so as to make the mount plate be supported by the plate supporter and fixing the plate supporter in the plate hole after adjusting the position of the mount plate horizontally and vertically within the plate hole; and mounting the mount members to the mount plates fixed in the plate holes respectively and mounting the device on the beam member via the mount members.