An image processing apparatus of the invention is for generating a tomographic image corresponding to a cross-section of an imaging object. The image processing apparatus 1 comprises: a data acquisitor 20 which obtains image data corresponding to a plurality of imaging with respect to the imaging object； and an image generator 30 which generates the tomographic image corresponding to the cross-section parallel to the depth direction based on the image data. The plurality of imaging are performed with mutually different focus positions in a depth direction and imaging ranges overlapped in the depth direction. The image generator 30 sets a value of each pixel in the tomographic image at a value obtained by a calculation process between the image data of a same position of the imaging object corresponding to the pixel obtained at each of the plurality of imaging.
