According to various embodiments of the disclosure, an electronic device may include a housing, a non-conductive supporting member disposed in the housing and including a first area, a second area spaced apart from the first area, and a third area connecting the first area and the second area, a conductive pattern portion disposed over the first area of the supporting member, a heat dissipation member disposed to at least partially overlap the conductive pattern portion, and an antenna including a circuit board, a conductive portion, and a ground portion. The conductive portion of the antenna may be disposed over the second area. The heat dissipation member may extend from the first area to the third area, and the ground portion of the antenna may extend from the second area to the third area to contact at least a portion of the heat dissipation member.