An electronic device including a first body, a second body, and at least one cavity antenna module is provided. The second body has a pivot side and a plurality of non-pivot sides, and the pivot side is connected pivotally to the first body. The cavity antenna module includes a metal cavity body and a first antenna structure. The metal cavity body is disposed in the second body and has an opening. A distance between one of the non-pivot sides and the metal cavity body is smaller than a distance between the pivot side and the metal cavity body, and the opening faces the one of the non-pivot sides. The first antenna structure is disposed in the opening of the metal cavity body, and the first antenna structure includes a feeding portion, a radiating portion, and a ground portion connected with one another.