In a case of a camera array, the arrangement of image capturing units and the arrangement of captured images that are displayed do not agree with each other depending on the orientation of the camera at the time of image capturing and it is hard to grasp the correspondence relationship between both. An image processing device for processing a plurality of images represented by captured image data obtained by a camera array image capturing device including a plurality of image capturing units includes a determining unit configured to determine, on the basis of a display angle of the images in a display region, an arrangement of each image in the display region corresponding to each of the plurality of image capturing units, and the arrangement of each image in the display region is determined based on the arrangement of the plurality of image capturing units.