The heat fixing apparatus includes a fixing heater and a pressure roller. The fixing heater has a plurality of resistance-type heat generation layers which are different in heat distribution in the longitudinal direction perpendicular to the direction of conveying a recording material. The recording material P is heated when passed through a fixing nip portion formed between the fixing heater and the pressure roller. The pressurization conditions between the fixing heater and the pressure roller can be changed. The heat fixing apparatus includes a fixing member which adjusts the lengthwise heat distribution of the fixing heater by changing the applied current proportion of the plurality of resistance-type heat generation layers according to the pressurization conditions between the fixing heater and the pressure roller.