An image forming apparatus includes a controller including a primary heating control portion that determines a first amount of power supplied to a heater based on a temperature of a fixing rotator detected by a temperature detector and controls the heater to perform a primary heating to heat the fixing rotator with the first amount of power, a secondary heating control portion that controls the heater to perform a secondary heating to heat the fixing rotator with a preset second amount of power, and a switch portion that controls the heater to switch between the primary heating and the secondary heating during an identical print job without changing a target temperature of the fixing rotator.