An image processing apparatus of the present invention includes an image obtaining unit obtaining first and second three-dimensional images, a deformation information obtaining unit obtaining deformation between two images, a cross-sectional image generating unit generating first and second cross-sectional images, a target position obtaining unit obtaining a target position in the first cross-sectional image, a corresponding position obtaining unit obtaining a corresponding position in the second three-dimensional image which corresponds to the target position on the basis of the deformation information.