An electronic device comprising: a printed circuit board including a first region and a second region, wherein the second region is adjacent to the first region; a first electronic element disposed in the first region; a second electronic element disposed in the second region; a first cover configured to shield the first electronic element, the first cover including a top surface in a size corresponding to the first region and a side surface bending along a rim of the top surface to a certain height, said first cover further having a facing boundary portion that is formed by alternating protrusion portions and recess portions; and a second cover configured to shield the second electronic element, the second cover including a top surface in a size corresponding to the second region and a side surface bending along a rim of the top surface to a certain height, said second cover further having a facing boundary portion that is formed by alternating protrusion portions and recess portions; a ground line formed or mounted on the printed circuit board and exposed on a top surface of the printed circuit board (4,) wherein the ground line is electrically connected to a ground portion of the printed circuit board, said ground line including a first ground line for closing along the side surface of the first cover, a second ground line for closing along the side surface of the second cover, and a boundary ground line for separating the first region and the second region, wherein the boundary ground line is formed along the boundary facing portions of the first cover and the second cover; wherein the first cover is fixed to electrically connect to the first ground line and wherein the second cover is fixed to electrically connect to the second ground line; wherein the protrusion portions of the second cover are inserted into respective recess portions of the first cover and wherein the protrusion portions of the first cover are inserted into respective recess portions of the second cover so that the first cover and the second cover tightly face each other; wherein at least one of the protrusion portions and the recess portions of the first cover and the second cover are formed to have a closed end; and wherein the facing boundary portion of the first cover and the facing boundary portion of the second cover are received in the single boundary ground line. a printed circuit board including a first region and a second region, wherein the second region is adjacent to the first region; a first electronic element disposed in the first region; a second electronic element disposed in the second region; a first cover configured to shield the first electronic element, the first cover including a top surface in a size corresponding to the first region and a side surface bending along a rim of the top surface to a certain height, said first cover further having a facing boundary portion that is formed by alternating protrusion portions and recess portions; and a second cover configured to shield the second electronic element, the second cover including a top surface in a size corresponding to the second region and a side surface bending along a rim of the top surface to a certain height, said second cover further having a facing boundary portion that is formed by alternating protrusion portions and recess portions; a ground line formed or mounted on the printed circuit board and exposed on a top surface of the printed circuit board (4,) wherein the ground line is electrically connected to a ground portion of the printed circuit board, said ground line including a first ground line for closing along the side surface of the first cover, a second ground line for closing along the side surface of the second cover, and a boundary ground line for separating the first region and the second region, wherein the boundary ground line is formed along the boundary facing portions of the first cover and the second cover; wherein the first cover is fixed to electrically connect to the first ground line and wherein the second cover is fixed to electrically connect to the second ground line; wherein the protrusion portions of the second cover are inserted into respective recess portions of the first cover and wherein the protrusion portions of the first cover are inserted into respective recess portions of the second cover so that the first cover and the second cover tightly face each other; wherein at least one of the protrusion portions and the recess portions of the first cover and the second cover are formed to have a closed end; and wherein the facing boundary portion of the first cover and the facing boundary portion of the second cover are received in the single boundary ground line.