The magnetocaloric heat generator (1) comprises at least two magnetocaloric elements (2, 12) arranged in succession and making up at least two consecutive thermal stages crossed by separate heat transfer fluids and comprising each two opposite ends (3 and 4, 13 and 14), a magnetic arrangement intended for subjecting each magnetocaloric element (2, 12) to a variable magnetic field, alternately creating a heating cycle and a cooling cycle in each magnetocaloric element (2, 12), a mechanism (8) for circulating the heat transfer fluids through the magnetocaloric elements alternately towards one end and towards the opposite end and vice versa, in synchronization with the variation of the magnetic field. The magnetocaloric elements (2, 12) are connected thermally two by two at their consecutive ends (4, 13) through the intermediary of a heat exchange mechanism (5) in thermal contact respectively with the heat transfer fluid circulating in the first (2) of the magnetocaloric elements and with the heat transfer fluid circulating in the second (12) of the magnetocaloric elements.