PROBLEM TO BE SOLVED: To provide a bed apparatus including a lifting/lowering drive unit capable of reliably liftingly/loweringly driving a bed frame by the small number of components.SOLUTION: The lifting/lowering drive unit includes: lifting/lowering movable bodies 3 each of which has one end and the other end, where the one end is movably provided to a bed frame 1 drive sources each of which has a rotatingly-driven output shaft 16 and is provided integrally with the lifting/lowering movable body at a middle of the lifting/lowering movable body, with an axis fitted along the width direction of the bed frame holding members 11 each of which rotationally holds the other end of the lifting/lowering movable body and immovably with respect to the bed frame and drive bodies 21 each of which has one end connected to the output shaft and the other end rotationaly connected to the bed frame, and that, when the output shaft is rotatingly driven, is liftingly/loweringly driven with respect to the lifting/lowering movable body and liftingly/loweringly drives the bed frame along with the lifting/lowering movable body.SELECTED DRAWING: Figure 1
