An image forming device and a controlling method thereof, in which the image forming device includes: a customer replaceable unit memory (CRUM) associated with a recording material storage medium to store a color conversion table group including a color conversion table that corresponds to status information of the image forming device, and a controller to determine current status information of the image forming device, to read a target color conversion table from among the color conversion table group according to the determined current status information, and to apply the target color conversion table to perform a printing operation on a document. Therefore, an optimum print quality can be guaranteed according to the determined current status of the image forming device.