An image forming apparatus includes plural internal devices, a controller, and a communication path. The controller is configured to control the plural internal devices. The communication path is used for communication between the plural internal devices and the controller. Usage priority of the communication path is assigned to plural pieces of communication between the plural internal devices and the controller in a time divisional manner. The controller detects a status change of the image forming apparatus, and upon detecting the status change, interrupts the time divisional manner with a time slot of a specific internal device among the plural internal devices, the specific internal device corresponding to the status change.