The present invention relates to an articulated bed which comprises a perimetric tubular frame, two mattress support portions articulated at the ends opposite to the respective ends of the frame, and articulated to one another at facing ends by means of a common rotating shaft; a geared motor assembled in the frame which rotationally operates a transverse shaft provided with at least one crank coupled by means of a connecting rod with the common shaft for the articulation of the two mattress support portions, transmitting a vertical oscillation to the common shaft and to the facing ends of the mattress support portions. In one embodiment variant it comprises a second geared motor which transmits an longitudinal alternating movement to the mattress support portions by means of a connecting rod-crank mechanism.