A fixing device includes a roller, a plurality of heaters, a temperature detection unit, and a control unit, wherein when the temperature detection unit detects that the temperature of longitudinal end portions of the roller is lower than a preset reference temperature, the control unit performs full-lighting control on the heater with the largest amount of heat supply to the end portions of the roller, out of the plurality of heaters, and performs lighting control on the heater with the second largest amount of heat supply to the end portions of the roller in a pattern at a predetermined duty ratio, or performs lighting control on the heater with the largest amount of heat supply to the end portions of the roller in a pattern at a predetermined duty ratio, and turns off the heater with the second largest amount of heat supply to the end portions of the roller.