An image forming device which is arranged to execute an authentication print job. The image forming device includes: a communication interface unit which receives print data; a job data holding unit which holds job data for the an authentication print job based on the print data; a job execution unit which executes a job based on the job data; an authentication unit; a user authentication unit which outputs a user authentication result; a control unit which instructs a start of execution of the authentication print job to the job execution unit based on the user authentication result; and an instruction generation unit which outputs to the control unit an instruction to change a setting with respect to the authentication print job based on an input of a user authentication result, wherein: the instruction generation unit outputs the instruction to change the setting with respect to an authentication print job in an execution state or an execution queuing state based on the input of the user authentication result that is received in an after user authentication period; and the control unit executes a process of changing the setting based on the instruction.