An aroma-diffusing heating device includes a heating base, and an aroma capsule detachably accommodated in the heating base and heatable by the heating base to give off fragrance. The aroma capsule includes a heat-transfer container defining a top opening, an aromatic substance held in the heat-transfer container, and a breathing film bonded to the heat-transfer container in the top opening of the heat-transfer container. The breathing film has open spaces defined therein.
