An electronic device may include: a housing including a front plate oriented in a first direction, a rear plate oriented in a second direction opposite the first direction, and a side member enclosing at least a part of a space between the front plate and the rear plate. The electronic device further including a display disposed to be visible through the front plate; a printed circuit board disposed between the display and the rear plate; a support structure having a first face oriented in the first direction and supporting the display and a second face oriented in the second direction and supporting the printed circuit board; a conductive member disposed between the support structure and the rear plate; and a sealing structure disposed between the conductive member and the rear plate, the sealing structure extending along a periphery of the conductive member and formed in a closed curve shape.