A plane antenna comprises a substrate having a first surface and a second surface, a first radiating element, a first power feeding pattern connected to the radiating element, and a first non-power feeding loop type radiating element provided adjacent to the first radiating element, all disposed on the first surface of the substrate, and a second radiating element, a second power feeding pattern connected to the radiating element, and a second non-power feeding loop type radiating element provided adjacent to the second radiating element, all disposed on the second surface of the substrate.