An image decoding apparatus that performs decoding using motion compensation includes: a reference area specifying unit that specifies, prior to decoding performed on a block-by-block basis, a reference area that is an existing range of reference pixels in a reference picture based on a block on which motion compensation is to be performed; a decoded pixel memory which stores decoded pixel data; a reference pixel buffer that holds reference pixel data; a reference-pixel-reading control unit that copies pixel data of an area including the reference area specified by said reference area specifying unit, from said decoded pixel memory into said reference pixel buffer; a motion compensation unit that generates interpolation pixel data by performing the motion compensation using reference pixel data copied into said reference pixel buffer; and a pixel value decoding unit that generates decoded pixel data using the interpolation pixel data.