An image apparatus which minimizes temperature differences between end portions and a central portion of a print medium includes heater members having different heat distributions, a temperature detecting unit for detecting a temperature of an area where a print medium passes through, a heat controlling unit for controlling a fusing unit temperature by an individual heat controlling of the heater members based on the temperature detected by the temperature detecting unit, and a rate determination unit for determining a divisional rate of heat to be charged per unit time to the fusing unit by means of the heater members. The rate determination unit determines the divisional rate based on the fusing condition input and the heat controlling unit which controls the heater members individually on the basis of the divisional rate determined by the rate determination unit.