The disclosure provides a portable terminal including an electronic device and a case disposed thereon that provides water resistant, dust resistant, and insulation for the electronic device by proper positioning of an aperture of the electronic device that uses an area of the case as an antenna. The case includes a body part that comprises a main body with a metallic portion formed of a metallic material, and an auxiliary body disposed adjacent to the metallic portion, and at least a portion of the auxiliary body is used as an antenna for transmission and reception of signals. An insulation member is disposed between the at least a portion of the auxiliary body and the main body, and a bonding layer is disposed in at least one of an area between the insulation member and at least one area of the main body, or between the insulation member and the auxiliary body.