An electronic device may include thin antennas disposed proximate a rear or front surface. An antenna structure may be disposed at a portion of a first surface or a second surface of a non-metal structure within the device, and is electrically connected to the metal structure. The antenna structure may comprise: a first bonding layer attached to a portion of the first surface or the second surface, where an opening is formed in the first bonding layer at a location of the metal structure; a antenna element pattern arranged on the first bonding layer and electrically connected to the metal structure through the opening; a second bonding layer arranged on the antenna element pattern; and an insulation layer arranged on the second bonding layer.