The invention provides an image forming apparatus and a method of setting print medium and resloves a problem of poor operability when a print medium with an adhering surface is arranged on a conveying mechanism. The image forming apparatus is characterized in that a paper feeding portion (102) of a roll body (4) filled with the print medium (2) around which an adhering surface is wound, wherein stripping paper does not adheres to the adhering surface, a conveying portion (103) comprising a conveying belt (21) pulling the roll body (4) out of the print medium (2) and conveying opposite to an image forming mechanism, and an output conveyer (104) including a cutting unit (31) are integrally unitized as a sheet feed conveyance unit (106). The sheet feed conveyance unit (106) can be pulled out or in with respect to a device body (100) at least before reaching a position capable of filling the roll body (4) in a sheet feeder (101).