To control a treatment temperature by measuring temperatures in a plurality of points inside a wafer face.

In a batch-system vertical hot wall-type heat treatment apparatus 10, radiation thermometers 50 which penetrate the sidewall of a process tube 11 are inserted between each upper wafer 1 and each lower wafer 1 which are held by a boat 21 in a treatment chamber 14, and central parts and peripheral parts on the rear surfaces of the wafers 1 are faced sequentially. The radiation thermometers 50 are connected to a temperature controller 33. The temperature controller 33 is constituted in such a way that a heater 32 is feedback-controlled by measuring the temperatures from the radiation thermometers 50. Consequently, the present actual temperature in the central parts and that in the peripheral parts of the wafers are measured respectively, and the heater is feedback-controlled. The temperature difference between the central parts and the peripheral parts of the wafers can be eliminated during a heat treatment or in a temperature rise and a temperature drop, and the uniformity of a treatment state distribution inside the wafer face can be enhanced.