An array antenna device according to an embodiment of the present invention includes an array antenna, a core layer, and a first adhesive layer. The array antenna has a first surface on which one or more radiating elements are disposed. The core layer is disposed facing the first surface. The first adhesive layer is present between the array antenna and the core layer and bonds the array antenna and the core layer to each other. The first adhesive layer includes one or more first openings and one or more radiating elements are disposed inside the first opening.