An image processing apparatus can acquire a plurality of pieces of visual point image data having different visual points from an imaging element having a pupil division pixel, and perform a gradation process on an image. When there are a plurality of types of high-brightness-side gradation distributions which can be reflected at a developing time, the image processing apparatus displays a user interface screen on a display unit and displays a histogram representing brightness of an image for each high brightness gradation improvement method. An area in which high brightness gradation is adjustable is displayed on a displayed image to be distinguished for each of the high brightness gradation improvement methods and for each setting condition.