Various embodiments of the present invention relate to an electronic device including a stacked circuit board. The electronic device comprises: a first circuit board; a second circuit board; one or more circuit elements disposed on the second circuit board; and a connecting member disposed between the first circuit board and the second circuit board facing the first circuit board to form an internal space surrounding at least some of the one or more circuit elements, and to electrically connect the first and second circuit boards, wherein the internal space may be filled with a phase change material (PCM) that absorbs heat generated by the at least some circuit elements to change the state of the material. Various other embodiments of the present invention may be additionally provided.