An electronic device comprising: a first cover; a second cover opposite the first cover; a side housing disposed between the first cover and the second cover, the side housing including a plate provided between the first cover and the second cover and a frame surrounding the plate and connected with the first cover and the second cover; a display disposed between the plate and the first cover; and a printed circuit board disposed between the plate and the second cover, the printed circuit board including a first surface facing the plate, a second surface facing the second cover, and side surfaces between the first surface and the second surface, wherein at least some of the side surfaces include plated areas (154, 354); wherein the plate includes a connection structure (220, 230, 240) to which the printed circuit board is electrically connected, the connection structure (220, 230, 240) including a recess (226, 236, 246), the recess (226, 236, 246) including a first sidewall (221, 231, 241), a second sidewall (222, 232, 242) facing the first sidewall (221, 231, 241), a first conductive structure (2281, 264, 2481) comprising a conductive material disposed on the first sidewall (221, 231, 241), and a second conductive structure (2282, 264, 2482) comprising a conductive material disposed on the second sidewall (222, 232, 242), wherein at least part of the printed circuit board is disposed in the recess (226, 236, 246) such that the plated areas (154, 354) contact the first conductive structure (2281, 264, 2481) and the second conductive structure (2282, 264, 2482), and wherein the plate includes a metal portion, and the metal portion is electrically connected with a ground area of the printed circuit board through the first conductive structure (2281, 264, 2481) and the second conductive structure (2282, 264, 2482). a first cover; a second cover opposite the first cover; a side housing disposed between the first cover and the second cover, the side housing including a plate provided between the first cover and the second cover and a frame surrounding the plate and connected with the first cover and the second cover; a display disposed between the plate and the first cover; and a printed circuit board disposed between the plate and the second cover, the printed circuit board including a first surface facing the plate, a second surface facing the second cover, and side surfaces between the first surface and the second surface, wherein at least some of the side surfaces include plated areas (154, 354); wherein the plate includes a connection structure (220, 230, 240) to which the printed circuit board is electrically connected, the connection structure (220, 230, 240) including a recess (226, 236, 246), the recess (226, 236, 246) including a first sidewall (221, 231, 241), a second sidewall (222, 232, 242) facing the first sidewall (221, 231, 241), a first conductive structure (2281, 264, 2481) comprising a conductive material disposed on the first sidewall (221, 231, 241), and a second conductive structure (2282, 264, 2482) comprising a conductive material disposed on the second sidewall (222, 232, 242), wherein at least part of the printed circuit board is disposed in the recess (226, 236, 246) such that the plated areas (154, 354) contact the first conductive structure (2281, 264, 2481) and the second conductive structure (2282, 264, 2482), and wherein the plate includes a metal portion, and the metal portion is electrically connected with a ground area of the printed circuit board through the first conductive structure (2281, 264, 2481) and the second conductive structure (2282, 264, 2482).