The present disclosure provides an antenna, an array antenna, a radio communication module, and a radio communication device of a new type. An antenna according to one example of embodiments of the present disclosure includes a radiation conductor, a ground conductor, a first feeding line, a second feeding line, a third feeding line, a fourth feeding line, a first feeding circuit, and a second feeding circuit. The first feeding line to the fourth feeding line are configured to be electromagnetically connected to the radiation conductor. The first feeding circuit is configured to feed reversed-phased signals, which have mutually opposite phases, to the first feeding line and the third feeding line. The second feeding circuit is configured to feed reversed-phased signals, which have mutually opposite phases, to the second feeding line and the fourth feeding line. The radiation conductor is configured to be excited in a first direction due to the feed from the first feeding line and the third feeding line. The radiation conductor is configured to be excited in a second direction due to the feed from the second feeding line and the fourth feeding line.