An image scanning device has an image sensor including a plurality of arrayed light receiving elements; a light source for shining light upon a scanning object; a lens unit for guiding reflected light from a scanning object to the image sensor and having a plurality of rod lens arrays, in which a plurality of rod lenses are arrayed, joined together; and a correction unit for generating image data based on the output values from the light receiving elements of the image sensor and correcting the pixel values of pixels in the image data corresponding to a position of a joint section between rod lens arrays so that the pixel values become darker.