An assistance device includes a rotary table provided on a floor surface of a room and being rotatable about an axis parallel to the vertical direction, a slide member provided on the rotary table and being slidable in the horizontal direction, and a support member provided on a slide member and supporting an upper body of a care receiver. The slide member slides the support member between a position outside the room, where the care receiver gets on and off the support member, and a position inside the room, where the care receiver supported by the support member is in a state of being placed in the room.