1. An image display apparatus configured to display an image based on an input image signal, the image display apparatus comprising: an adjustment unit configured to adjust a display image based on an adjustment parameter; a display unit configured to generate a plurality of adjustment parameter candidates different from each other and display a list of a plurality of adjusted images adjusted by the adjustment unit based on the plurality of adjustment parameter candidates; and a selection unit configured to select an adjusted image from the displayed list, wherein the adjustment parameter is set based on the adjusted image selected from the plurality of adjusted images and the plurality of adjustment parameter candidates when displaying an image.