Antenna device, and wireless communication device

An antenna device comprising:

• a feeding antenna element configured to be electrically connected at one end to a supply source configured to supply a wireless communication signal, the feeding antenna element including an element section parallel to a ground surface;
• and
• a parasitic antenna element including a vertical element section disposed perpendicularly to the ground surface, the parasitic antenna element being disposed apart from another end of the feeding antenna element by a predetermined distance, wherein
• the parasitic antenna element includes two parallel element parts disposed in parallel with the ground surface, wherein each of the two parallel element parts includes a plurality of parallel element sections,
• the plurality of parallel element sections are connected to each other at ends thereof in such a way that at least two of the parallel element sections form a right angle,
• each of the two parallel element parts is connected to each end of the vertical element section in such a way that each angle formed with the vertical element section is at right angle, respectively, and
• one of the plurality of parallel element sections of one of the two parallel element parts is disposed parallel to the element section parallel to the ground surface of the feeding antenna element at a position facing the feeding antenna element and is disposed apart from the feeding antenna element by the predetermined distance.