PURPOSE: To perform the movement and rehabilitation of a joint to a bedridden patient, by dividing a bed into two or more support plates and reciprocatingly moving a predetermined support plate in matching relation to the moving direction of the joint part of a human body.

CONSTITUTION: A bed apparatus is equipped with a base 1, the bed plate 10 supported on the base 1 by a support 2 and drive means 100, 200 for partially driving the bed plate 10. The bed plate 10 is divided into two or more sections in the stature direction of a human body A to form support plates 11W14 which are, in turn, connected by hinges 15W17. The drive means 100, 200 rotationally drive the predetermined support plates 11W14 of the bed plate 10 in the moving direction of the joint part of the human body A.