The disclosed antenna includes: a core-wire-side feeding point and a ground-side feeding point which are provided in a row in proximity to one another on the surface of a window glass close to an opening in a metal flange of an automobile window; a ground-side element including a filament that extends in a direction away from the metal flange located closest to the ground-side feeding point; and a core-wire-side element including a core-wire-side first filament that extends from the core-wire-side feeding point substantially in parallel with the filament of the ground-side element, and a core-wire-side second filament that branches from the core-wire-side first filament or that extends directly from the core-wire-side feeding point in parallel with the core-wire-side first filament. The length from the core-wire-side feeding point to the tip of the core-wire-side first filament and the length from the core-wire-side feeding point to the tip of the core-wire-side second filament are set to filament lengths respectively having two discrete resonant frequencies that resonate within a single frequency bandwidth.
