<p>An image forming apparatus for forming an image on a recording medium, comprising an image bearing member; an image forming means for forming an image on the image bearing member; a transfer means for transferring the image formed on the image bearing member by the image forming means onto a recording medium; a heat fixing means for fixing the image transferred to the recording medium by the transfer means onto the recording medium; a power source; and a control means for detecting a temperature increased condition of the heat fixing means when the power source is turned ON and for determining a temperature adjust temperature of the heat fixing means at a fixing operation in accordance with the detected result. <IMAGE></p>