An image fixing apparatus that senses temperature of a heater and controls the temperature accurately includes a pair of fixing rollers, a heater housed inside at least one of the pair of fixing rollers, and a sensor integrally formed with the heater to detect temperatures of the heater from a plurality of sensing positions. The sensor includes an array of sensing units connected in parallel to the plurality of sensing positions, and generates one sensing signal. An image forming apparatus includes the image forming apparatus. An image fixing temperature control method includes generating average temperature information of a heater; and controlling the driving of the heater based on the temperature information.