A heat radiation sheet includes: a film layer; a heat radiation layer on the film layer and having a first area, a second area, and a third area and a plurality of openings therein; and a first adhesive layer on the heat radiation layer. The openings include a plurality of first openings in the first area, a plurality of second openings in the second area, and a plurality of third openings in the third area, and an average distance between adjacent ones of the first openings is smaller than an average distance between adjacent ones of the third openings.