According to an embodiment of the disclosure, an electronic device (100) includes: a transparent front surface plate (320) defining at least a portion of a front surface of the electronic device (100); a rear surface plate (380) defining at least a portion of a rear surface of the electronic device (100); a side surface housing (810) surrounding at least a portion of a space between the front surface plate (320) and the rear surface plate (380); a support (820) disposed in the space and connected with the side housing (810) or integrally formed with the side housing (810), the support (820) comprising a first border (811) and a second border (812) disposed on opposite sides, a third border (813) connecting one end of the first border (811) and one end of the second border (812), and a fourth border (814) connecting another end of the first border (811) and another end of the second border (812), the fourth border (814) being disposed opposite the third border (813); a display (330) disposed in the space and viewable through at least a portion of the front surface plate (320); a second flexible printed circuit board (FPCB) (1030) disposed to at least partially overlap the display (330) when viewed above the front surface plate (320); a first FPCB (1040) connecting the display (330) and the second FPCB (1030), and disposed in a folded state within a specified proximity of the fourth border (814) and having a portion overlapping the display (330) when viewed above the front surface plate (320); a first sealing member (700) disposed between the first FPCB (1040) and the support (820), or between the second FPCB (1030) and the support (820), and extending from a first end to a second end along the fourth border (814); a second sealing member (460) disposed between the display (330) and the support (820), and extending from a third end proximate the first end to a fourth end proximate the second end along the first border (811), the third border (813), and the second border (812); and a third sealing member (950) disposed between the first end of the first sealing member (700) and the third end of the second sealing member (460), and between the second end of the first sealing member (700) and the fourth end of the second sealing member (460), and connecting the first sealing member (700) and the second sealing member (460).