IMAGE FORMING APPARATUS

PROBLEM TO BE SOLVED: To enable changing of a period required for applying a post-process without changing a speed of forming an image on a sheet by an image forming apparatus.SOLUTION: An image forming system 1 includes: an image forming apparatus 2; a reception roll 31 for receiving a sheet output from the image forming apparatus 2 at a predetermined feeding speed and feeding the sheet downstream at a predetermined feeding speed; a binder 40 for applying a post-process to the sheet; a reception sensor 32 for recognizing a time interval of the image forming apparatus 2 outputting sheets; and a reception sensor 32 for recognizing no output sheet being restrained by the image forming apparatus 2. Further, the reception roll 31 feeds the sheet at a feeding speed different from the predetermined feeding speed after the reception sensor 32 recognizes no sheet being restrained by the image forming apparatus 2 in accordance with the time interval recognized by the reception sensor 32.