An image processing apparatus includes: a detection unit configured to detect images of interest including regions of interest that are estimated as an object to be detected, from a group of a series of images acquired by sequentially imaging a lumen of a living body; an image-of-interest group extracting unit configured to extract a group of images of interest including an identical region of interest, from the images of interest detected by the detection unit; and a representative image extracting unit configured to extract one or more representative images from the group of images of interest, based on at least one of correlation of the regions of interest with the object to be detected, and visibility of the regions of interest.