An electronic device according to various embodiments includes a mmWave antenna module including a plurality of first antenna elements disposed on a first surface that is oriented in a first direction, a first coupling unit that protrudes in a second direction from a second surface that is perpendicular to the first surface and is oriented in the second direction, and an RFIC disposed on a third surface oriented in a third direction opposite to the first direction. The electronic device also includes an antenna structure including a plurality of second antenna elements and a second coupling unit protruding from one surface of the antenna structure; a connection member electrically connected to at least one of the first coupling unit and the second coupling unit; a main PCB electrically connected to the mmWave antenna module; and a wireless communication circuit disposed on the main PCB.