An image editing system having an image forming apparatus and an expansion box. The image forming apparatus includes an image inputting part which inputs the original image as an image, an image processing part which converts image information of an input color coordinate system into an output color coordinate system, an image outputting part which prints out image information of the output color coordinate system, and a first connection part which performs exchanging the image information of the output color coordinate system between the image forming apparatus and an external device. The expansion box includes a second connection part which is connected with the first connection part and a storing part which stores the image information and provides the expansion of image editing function.