An image forming apparatus includes a communication interface unit to receives an XML paper specification (XPS) file, an XPS file processing unit which converts the XPS file into an output data corresponding to printing paper to print the XPS file using information regarding the height and width of a FixedPage in the XPS file, and a control unit which controls the image forming apparatus to print the output data. Accordingly, even when an XPS file does not include information regarding printing paper, a user can select and print printing paper suitable for the user's demand.