PURPOSE: To change a posture to a posture of going down and standing on a floor surface from a posture of lying on one's back by arranging a bed part so as to be capable of standing up in a chair shape as well as to be horizontally rotatable to a fixed frame, and constituting it so as to be properly ascendable and descendable.

CONSTITUTION: In a bed freely ascendable and descendable by an ascending and descending device built in a fixed frame 1a, when a push-button switch of a hand side operation switch box is operated from an ordinary use condition, a back part support frame to receive a mat 47 is stood up and rotated by extensible driving of an extensible-contractile lever using a stepping motor as a driving source, and the bed is converted into a chair shape. Next, when a patient on the bed is stood up on one side of the bed, after the rotation preventing regulation by a rotation preventive means is released, a rotary frame 24 supported on a rotary mechanism 25 is rotated by 90 degrees. Next, the back part support frame is also put in a standing erect condition, and a tip part converts a waist part support frame into a slightly downward inclined condition, and puts it in an easily standing-up condition.