A card structure includes a first element and a second element. The first element includes a first peripheral portion and a plurality of first contact points exposed by the first peripheral portion. The second element includes a second peripheral portion and a plurality of second contact points corresponding to the first contact points of the first element and exposed by the second peripheral portion. When the first and second elements are joined with each other, the first peripheral portion of the first element and the second peripheral portion of the second element are adjacent to each other, to juxtapose the first contact points of the first element and the second contact points of the second element to each other. The juxtaposed first and second contact points of the first and second elements are coupled to each other by a welding portion.