In a fixing apparatus provided with a plurality of fixing heaters having heat distribution characteristics that are different from each other inside a fixing roller, and an image forming apparatus provided with the fixing apparatus, an auxiliary heater is provided, the auxiliary heater being provided inside the fixing roller and to which power is distributed only during the warm-up period until the fixing roller in a lower temperature state reaches a predetermined fixing temperature. The plurality of fixing heaters includes a first fixing heater having first heat distribution characteristics that mainly heats a center portion of the fixing roller, and a second fixing heater having second heat distribution characteristics that mainly heats both end portion regions of the fixing roller.