A fixing apparatus includes a fixing device, a temperature sensor, a storage device, and a control device. The control device selects, before start of power supply to a heater of the fixing device, a temperature characteristic of an initial temperature the same as or approximate to a temperature of a nip region detected by the temperature sensor, out of respective temperature characteristics of a plurality of initial temperatures stored in the storage device, calculates a predicted temperature that may be reached a prescribed time after the start of power supply to the heater, on a basis of the selected temperature characteristic, and increases the power to the heater by a predetermined first value, when a temperature, detected by the temperature sensor the prescribed time after the start of power supply to the heater, is lower than the predicted temperature.