An image forming apparatus comprises a fusing device for heating and fixing an unfixed image on a recording material while feeding the recording material, reversing device for reversing the recording material after passing the fusing device. The image forming apparatus operates in a first mode in which the recording material which passed the fusing device is ejected to an ejection section directly without being reversed, and a second mode in which the recording material which passed said fusing device is ejected to an ejection section after being reversed by the reversing device. A throughput of the recording material fed and/or the fusing temperature of the fusing device in the first mode being smaller or lower during at least part of an image forming process than in the second mode. With this image forming apparatus, the recording materials can be stacked in the ejection portion with improved quality and an excessive rise of temperature in the vicinity of the ejection portion can be avoided.