Provided is an image processing apparatus or the like, which is able to accurately distinguish an abnormality from another object having the same type of color information as that of the abnormality. An image processing apparatus 1 includes: an abnormality candidate region identifying unit 110 that identifies a candidate region for an abnormality from an image obtained by imaging inside of a lumen of a living body a surrounding region determining unit 120 that determines a surrounding region surrounding the candidate region a shape information calculating unit 130 that calculates shape information of the candidate region and surrounding region in a depth direction with respect to a screen and an abnormality region determining unit 140 that determines, based on a correlation between the shape information of the candidate region and the shape information of the surrounding region, whether or not the candidate region is an abnormality.
