A magnetocaloric heat generator (10) comprising at least one magnetocaloric element (2) with a first and second ends (3, 4), a magnetic arrangement for subjecting the magnetocaloric element (2) to a variable magnetic field, alternately creating heating and cooling cycles in the magnetocaloric element (2), a mechanism for circulating a heat transfer fluid through the magnetocaloric element (2) alternately towards the first and second ends (3, 4) and vice versa in synchronisation with the variation of the magnetic field, and at least one energy exchange mechanism (15). This heat generator (10) is crossed in one direction by the heat transfer fluid entering the magnetocaloric element (2) through one of the ends (3, 4) during a heating or cooling cycle and to be crossed in the opposite direction by the heat transfer fluid exiting the magnetocaloric element (2) through the same end (3, 4) during the other cooling or heating cycle.