An image forming apparatus includes a main body having an image forming portion, a scan unit having an image sensor and connected to the main body so as to transmit and receive a signal to and from the main body, and a moving unit disposed at least one of the main body and the scan unit so that the scan unit is relatively moved with respect to the main body. Therefore, a space of a discharged portion formed between the main body and the scan unit can be efficiently utilized, and a jammed paper can be facilely removed.