A vacuum heating device comprises: a pot body having an inner casing and an outer casing; a vacuum space being formed between the inner casing and the outer casing; a heat source installed at a lower outer side of the inner casing; a pot cover installed at a top of the pot body; the pot cover having a vent hole; the pot cover tightly covering the receiving space of the inner casing so as to have a preferred heat preservation effect; and an energy supply device for actuating the heat source to generate heat to heat the inner casing. The energy supply device is a conductor body which is connected to the heat source. Or the energy supply device is an electromagnetic generator installed at a lower side of the pot body.