A bed supporting device adapted to be installed to a bottom seat of a bed includes a leg unit； a first link board connected to an upper end of the leg unit, and formed with a first through hole； and a second link board for connection to the bottom seat, installed on the first link board and formed with a second through hole corresponding to the first through hole； wherein, either the first or second through hole is elongated such that a fixing screw can extend through the first and second through holes in the first and second link boards for coupling a fastener, thereby immobilizing the first and second link boards.
