There is provided an image forming device that includes a conveyor section, an image forming section, an accessing section and a control unit. The conveyor section conveys recording media in a conveying path, the recording media including a recording medium having a data storage unit attached thereto and a recording medium with no data storage unit attached thereto, the data storage unit storing data or being capable of storing data. The image forming section forms an image on the recording medium. The accessing section is disposed at an access position along the conveying path and accesses the data storage unit to execute an access operation to write data into or read data from the data storage unit. The control section is configured to control the conveyor section and the accessing section to bring the recording medium having passed the access position back to the access position and to access the data storage unit attached to the recording medium which has brought back to the access position to execute a re-access operation to write unprocessed data into or read unprocessed data from the data storage unit, the unprocessed data being such data that remained unprocessed with the access operation.