A technique which enables reduction of time required for continuous printing performed by an image forming apparatus in a temperature rise suppression mode. A printer prints a plurality of pages based on print data received from a host computer. A temperature sensor detects internal temperature of the printer. A control unit controls the printer such that the printing is suspended when the internal temperature has risen to a shifting temperature, and the printing is restarted when the internal temperature has fallen to a normal restart threshold value during the suspension of the printing. The control unit calculates the number of remaining pages left unprinted when the printing is suspended, and sets the normal restart threshold value according to the calculated number of the remaining pages.