An image processing apparatus includes an area setter configured to set a target area in a first image among a plurality of captured images acquired by imaging at different time from each other, an area detector configured to detect a corresponding area relevant to the target area in a plurality of second images among the plurality of captured images, a focus state acquirer configured to acquire focus states of the target area and the corresponding area, and a classification processor configured to perform classification processing that classifies the plurality of captured images into a plurality of groups according to the focus states.