According to an embodiment of the disclosure, an electronic device includes: a transparent front surface plate defining at least a portion of a front surface of the electronic device, and including a first edge and a second edge disposed on opposite sides, a third edge connecting one end of the first edge and one end of the second edge, and a fourth edge connecting another end of the first edge and another end of the second edge and disposed opposite the third edge; a rear surface plate defining at least a portion of a rear surface of the electronic device; a side housing surrounding at least a portion of a space between the front surface plate and the rear surface plate; a support disposed in the space and connected with the side housing or integrally formed with the side housing; a display disposed in the space and viewable through at least a portion of the front surface plate; a second flexible printed circuit board (FPCB) disposed to at least partially overlap the display when viewed above the front surface plate; a first FPCB connecting the display and the second FPCB, and disposed in a folded state within a specified proximity of the fourth edge and having a portion overlapping the display when viewed above the front surface plate; a first seal disposed between the first FPCB and the support, or between the second FPCB and the support, and extending from a first end to a second end along the fourth edge; a second seal disposed between the display and the support, and extending from a third end proximate the first end to a fourth end proximate the second end along the first edge, the third edge, and the second edge; and a third seal disposed between the first end of the first seal and the third end of the second seal, and between the second end of the first seal and the fourth end of the second seal, and connecting the first seal and the second seal.