An image forming apparatus and a method of controlling the image forming apparatus are provided. The method includes detecting a conflicting option that is impossible to be set simultaneously with a plurality of options selected for a job of the image forming apparatus, reflecting the detected conflicting option to display an option setting screen for the job of the image forming apparatus, and if a conflicting option is selected on the displayed option setting screen, displaying an option list user interface (UI) window in an area of the displayed option setting screen, wherein the option list UI window includes a replaceable option that replaces an option that is impossible to be set simultaneously with the conflicting option.