The present invention is directed providing a technique capable of reducing a time for stabilizing a temperature in a processing chamber. The technique includes: a substrate support configured to support a substrate; a thermal insulation unit disposed below the substrate support; a processing chamber configured to accommodate the substrate support and where the substrate is processed; a first heating unit disposed around the processing chamber and configured to heat an inside of the processing chamber from a lateral side thereof; and a second heating unit disposed between the substrate support and the thermal insulation unit inside the processing chamber, the second heating unit including a heater having a substantially annular shape and a suspending member extending downward from the heater, wherein a diameter of the heater is smaller than that of the substrate.