The present invention provides a multifunction bed that has a simple structure to allow its size to be reduced and that can be automatically changed between a bed form and a wheelchair form using very simple operations. This multifunction bed comprises a fixed U-shaped bed 1 having a U-shaped cut-out section 6 and a movable auxiliary bed 2 that is detachably fitted in the U-shaped cut-out section of the fixed U-shaped bed. The movable auxiliary bed can travel on underlying wheels 14 and 16 and can be changed between a bed form for a horizontal position and a wheelchair form having a backrest section 19, a seat section 20, and a leg-rest section 21. In order to prevent a person lying on the bed from being pushed forward while the movable auxiliary bed is being changed to the wheelchair form, the seat section is inclined according to the inclination of the backrest section so that part of the seat section closer to the leg rest section is located higher than the remaining part, thereby allowing the buttocks of the person lying on the bed to sink relative to the bed form.