To provide a bed device which has a simple structure and gives a slope in accordance with a body shape or taste to a prescribed floorboard with simple manual operation.

The bed device includes: the plurality of floorboards 3, 4, and 5 which are placed inside a bed frame 2 along a longitudinal direction and are each independently supported by the bed frame 2; a plurality of attachment holes 13 which are provided for the bed frame 2 or a bracket 8 integrated with the bed frame 2 and have different height; and a locking member 14 which engages with any of the plurality of attachment holes 13 in a disengageable manner and is abutted on the floorboards 3, 5 directly or indirectly to support the floorboard 3, 5. Selection of the attachment hole 13 to be engaged with the locking member 14 freely changes inclination of the floorboards 3, 5.