A heating device for heating a powder attached to a substrate, including a housing, a heating member, a cover, a fan, and a filter. The housing is provided with a heating cavity. The heating member is accommodated in the heating member, and is configured to heat the powder attached to the substrate after conveyed to the heating cavity. The cover is mounted on the housing, and covers the heating cavity. The fan is mounted on the housing, and an air extraction pipe is arranged between the fan and the heating cavity to enable the fan to extract air from the heating cavity. The filter is provided in the air extraction pipe.