An image processing system includes an image forming apparatus and first and second image processing servers connected to the image forming apparatus via a network, the first image processing server includes: a first image processor which performs a first image processing operation on target image data received from the image forming apparatus; and a protected area calculator which calculates a protected area to be prohibited from being processed next, which is related to the area processed by the first image processor, and generates image protection information including information of the protected area, and the second image processing server includes a second image processor which performs a second image processing operation on the areas excluding the protected area whose information is included in the image protection information generated by the protected area calculator.