Heat treatment is performed on a dummy wafer with halogen lamps or the like to perform dummy treatment of adjusting the temperature of in-chamber structures including a susceptor and the like. A dummy recipe for the dummy treatment is prepared in advance, and a maximum value and a minimum value each being a threshold for the number of times of dummy treatment are set. After the dummy treatment is started, the number of times of dummy treatment is counted. Comparison determination between the number of times of dummy treatment at the time point when carriers storing semiconductor wafers each to be a product are transported in to a heat treatment apparatus and the set maximum value and minimum value is performed. In this manner, the timing of the end of the dummy treatment and the start of the treatment of product wafers is adjusted.