An image forming apparatus capable of minimizing a temperature rise of a cover is disclosed. The image forming apparatus includes a main body, a fusing unit mounted in the main body to fuse an image to paper, a cover mounted to the main body to expose the fusing unit, a heat shielding member mounted proximate to an inner side of the cover to block heat transferred from the fusing unit, an external air circulation chamber formed between the heat shielding member and the cover, in which external air circulates by convection, and at least one external air flow hole, through which the air flows into/out of the external air circulation chamber.