An electronic device comprising: a housing that includes a first face, a second face that is directed opposite to the first face, and a side face that at least partially encloses a space between the first face and the second face; a first metallic member (314, 514, 914, 1214) configured to form a first portion of the side face, and includes a first end and a second end; a second metallic member (312, 512, 912, 1212) configured to form a second portion of the side face, and is positioned adjacent to the first end of the first metallic member and electrically insulated from the first metallic member; a third metallic member (311, 511, 911, 1211) configured to form a third portion of the side face, and is positioned adjacent to the second end of the first metallic member and electrically insulated from the first metallic member; a communication circuit that is electrically connected to at least one of the first metallic member, the second metallic member, and the third metallic member; at least one ground member that is included within the housing; a sensor (506, 906, 1206) configured to: detect if an external object comes in contact with at least one of the first metallic member, the second metallic member, and the third metallic member, generate a first signal when a contact of the external object with respect to at least one of the first metallic member or the second metallic member is detected, and generate a second signal when the contact of the external object with respect to the first metallic member and with respect to the second metallic member is not detected; and a circuit configured to: when the sensor generates the first signal, open an electric path between the first metallic member and the ground member such that a resonant path is formed in between the first metallic member and the third metallic member by a signal fed from the communication circuit, and when the sensor generates the second signal, connect the electric path between the first metallic member and the ground member such that a resonant path is formed in between the first metallic member and the second metallic member by a signal fed from the communication circuit. a housing that includes a first face, a second face that is directed opposite to the first face, and a side face that at least partially encloses a space between the first face and the second face; a first metallic member (314, 514, 914, 1214) configured to form a first portion of the side face, and includes a first end and a second end; a second metallic member (312, 512, 912, 1212) configured to form a second portion of the side face, and is positioned adjacent to the first end of the first metallic member and electrically insulated from the first metallic member; a third metallic member (311, 511, 911, 1211) configured to form a third portion of the side face, and is positioned adjacent to the second end of the first metallic member and electrically insulated from the first metallic member; a communication circuit that is electrically connected to at least one of the first metallic member, the second metallic member, and the third metallic member; at least one ground member that is included within the housing; a sensor (506, 906, 1206) configured to: detect if an external object comes in contact with at least one of the first metallic member, the second metallic member, and the third metallic member, generate a first signal when a contact of the external object with respect to at least one of the first metallic member or the second metallic member is detected, and generate a second signal when the contact of the external object with respect to the first metallic member and with respect to the second metallic member is not detected; and detect if an external object comes in contact with at least one of the first metallic member, the second metallic member, and the third metallic member, generate a first signal when a contact of the external object with respect to at least one of the first metallic member or the second metallic member is detected, and generate a second signal when the contact of the external object with respect to the first metallic member and with respect to the second metallic member is not detected; and a circuit configured to: when the sensor generates the first signal, open an electric path between the first metallic member and the ground member such that a resonant path is formed in between the first metallic member and the third metallic member by a signal fed from the communication circuit, and when the sensor generates the second signal, connect the electric path between the first metallic member and the ground member such that a resonant path is formed in between the first metallic member and the second metallic member by a signal fed from the communication circuit. when the sensor generates the first signal, open an electric path between the first metallic member and the ground member such that a resonant path is formed in between the first metallic member and the third metallic member by a signal fed from the communication circuit, and when the sensor generates the second signal, connect the electric path between the first metallic member and the ground member such that a resonant path is formed in between the first metallic member and the second metallic member by a signal fed from the communication circuit.