In an image encryption apparatus, an input processor inputs data of an input image. An encryptor encrypts a part or whole of the data of the input image. A marker generator generates data of a marker indicating an encrypted area. An image saver saves data of a marker-covered image covered with the marker. A marker sticker sticks the marker. An output processor outputs an encrypted image. In an image decryption apparatus, an input processor inputs data of an input image. A marker detector detects a marker and identifies an encrypted area. A decryptor decrypts data in the encrypted area. An image restorer restores data in an area covered with the marker by sticking data of a marker-covered image. An output processor outputs data of a decrypted image.