An electronic device (300, 600) comprising: a front cover (302, 602) and a rear cover (311, 611) forming a part of an outer appearance of the electronic device (300, 600); an array antenna comprising a plurality of antenna elements (510, 520, 530. 540) disposed between the front cover (302, 602) and the rear cover (311, 611); and a support member (320, 620) disposed between the front cover (302, 602) and the rear cover (311, 611), wherein the support member (320, 620) is configured to: support a display (301, 601) of the electronic device (300, 600), and extend to a lateral surface of the electronic device (300, 600) to form at least in part a lateral appearance of the electronic device (300, 600), the support member (320, 620) comprising: a conductive first portion (321, 621) forming the lateral appearance of the electronic device (300, 600); a second portion (3222, 622) adjacent to the array antenna, the front cover (302, 602), and the conductive first portion (321, 621), and comprising at least one opening filled with a non-conductive material; and a third portion (3224, 623) comprising a non-conductive material and disposed adjacent to the array antenna, the rear cover (311, 611), and the conductive first portion (321, 621), wherein the conductive first portion (321, 621) is exposed to an outside of the electronic device (300, 600), and the second portion (3222, 622) and the third portion (3224, 623) are hidden by the front cover (302, 602) and the rear cover (311, 611) so as not to be exposed to the outside, and wherein the array antenna is configured to radiate a beam to the outside through the at least one opening and the third portion (3224, 623). a front cover (302, 602) and a rear cover (311, 611) forming a part of an outer appearance of the electronic device (300, 600); an array antenna comprising a plurality of antenna elements (510, 520, 530. 540) disposed between the front cover (302, 602) and the rear cover (311, 611); and a support member (320, 620) disposed between the front cover (302, 602) and the rear cover (311, 611), wherein the support member (320, 620) is configured to: support a display (301, 601) of the electronic device (300, 600), and extend to a lateral surface of the electronic device (300, 600) to form at least in part a lateral appearance of the electronic device (300, 600), support a display (301, 601) of the electronic device (300, 600), and extend to a lateral surface of the electronic device (300, 600) to form at least in part a lateral appearance of the electronic device (300, 600), the support member (320, 620) comprising: a conductive first portion (321, 621) forming the lateral appearance of the electronic device (300, 600); a second portion (3222, 622) adjacent to the array antenna, the front cover (302, 602), and the conductive first portion (321, 621), and comprising at least one opening filled with a non-conductive material; and a third portion (3224, 623) comprising a non-conductive material and disposed adjacent to the array antenna, the rear cover (311, 611), and the conductive first portion (321, 621), wherein the conductive first portion (321, 621) is exposed to an outside of the electronic device (300, 600), and the second portion (3222, 622) and the third portion (3224, 623) are hidden by the front cover (302, 602) and the rear cover (311, 611) so as not to be exposed to the outside, and wherein the array antenna is configured to radiate a beam to the outside through the at least one opening and the third portion (3224, 623). a conductive first portion (321, 621) forming the lateral appearance of the electronic device (300, 600); a second portion (3222, 622) adjacent to the array antenna, the front cover (302, 602), and the conductive first portion (321, 621), and comprising at least one opening filled with a non-conductive material; and a third portion (3224, 623) comprising a non-conductive material and disposed adjacent to the array antenna, the rear cover (311, 611), and the conductive first portion (321, 621), wherein the conductive first portion (321, 621) is exposed to an outside of the electronic device (300, 600), and the second portion (3222, 622) and the third portion (3224, 623) are hidden by the front cover (302, 602) and the rear cover (311, 611) so as not to be exposed to the outside, and wherein the array antenna is configured to radiate a beam to the outside through the at least one opening and the third portion (3224, 623).