1. An image processing apparatus comprising: a first calculation unit adapted to calculate a feature amount of a search target image; a second calculation unit adapted to calculate a similarity between a feature amount of each image stored in a storage device and the feature amount calculated by said first calculation unit, thereby obtaining a plurality of candidate images similar to the search target image; and a display order determination unit adapted to determine a display order of the plurality of candidate images obtained by said second calculation unit on the basis of a log of a device selected as a reference target.