An antenna device and a transmitting and receiving unit using the device which are capable of simultaneously polarizing each direction of a plurality of beams are provided without increasing the size of the whole device. For example, when the detection is achieved by forming a plurality of beams such as a radar of monopulse type, the angle measurement range is easily extended. A movable part is provided with a plurality of primary radiators and movable part side transmission lines (dielectric strips of NRD guide) to be coupled therewith, and a fixed part side is provided with dielectric lenses to form each focal plane at the position of primary radiators, and fixed part side transmission lines (dielectric strips of NRD guide) to be respectively coupled with the movable part side transmission lines. A plurality of beams are simultaneously tilted by displacing the movable part.