An image forming apparatus according to an embodiment includes a paper supply unit. An image forming unit forms an image on paper supplied from the paper supply unit. A reading unit generates image information by reading an original document, the generated image information corresponding to the original document. An input unit receives input designation of a memo region in the generated image information. A control unit determines a color of the original document based on the generated image information. The image forming unit forms a memo image in the designated memo region on the paper supplied from the paper supply unit with a color different from the determined color of the original document.