A wireless terminal unit for wireless communications, the wireless terminal unit comprising: a wireless circuit board; an antenna element facing one of surfaces of the wireless circuit board; a ground conductor facing the other surface of the wireless circuit board; and a plurality of ground terminals (108, 109) electrically connecting the wireless circuit board with the ground conductor, wherein a first ground terminal, one of the plurality of ground terminals (108, 109), is disposed near a power supply part for supplying power from the wireless circuit board to the antenna element, and a second ground terminal, another one of the plurality of ground terminals (108, 109), is disposed on a second edge of the wireless circuit board, characterized in that: the first ground terminal is disposed on a first edge of the wireless circuit board, said first edge being at a first distance from a position in which the power supply part is connected with the wireless circuit board, said first distance being a distance which is less than or equal to 1/16 wavelength at the operating frequency; the wireless circuit board has a perimeter that is more than or equal to 1/2 wavelength and less than or equal to 1 wavelength at an operating frequency; the second edge is at a second distance that is more than or equal to 1/4 wavelength at the operating frequency from the first ground terminal; the ground conductor being a sheet metal conductor is larger in plane dimension than the wireless circuit board; and the wireless terminal unit further comprises: a short terminal for connecting the wireless circuit board with the antenna element, one end of the short terminal being electrically connected with a ground of the wireless circuit board and the other end of the short terminal is electrically connected with the antenna element. a wireless circuit board; an antenna element facing one of surfaces of the wireless circuit board; a ground conductor facing the other surface of the wireless circuit board; and a plurality of ground terminals (108, 109) electrically connecting the wireless circuit board with the ground conductor, wherein a first ground terminal, one of the plurality of ground terminals (108, 109), is disposed near a power supply part for supplying power from the wireless circuit board to the antenna element, and a second ground terminal, another one of the plurality of ground terminals (108, 109), is disposed on a second edge of the wireless circuit board, characterized in that: the first ground terminal is disposed on a first edge of the wireless circuit board, said first edge being at a first distance from a position in which the power supply part is connected with the wireless circuit board, said first distance being a distance which is less than or equal to 1/16 wavelength at the operating frequency; the wireless circuit board has a perimeter that is more than or equal to 1/2 wavelength and less than or equal to 1 wavelength at an operating frequency; the second edge is at a second distance that is more than or equal to 1/4 wavelength at the operating frequency from the first ground terminal; the ground conductor being a sheet metal conductor is larger in plane dimension than the wireless circuit board; and the first ground terminal is disposed on a first edge of the wireless circuit board, said first edge being at a first distance from a position in which the power supply part is connected with the wireless circuit board, said first distance being a distance which is less than or equal to 1/16 wavelength at the operating frequency; the wireless circuit board has a perimeter that is more than or equal to 1/2 wavelength and less than or equal to 1 wavelength at an operating frequency; the second edge is at a second distance that is more than or equal to 1/4 wavelength at the operating frequency from the first ground terminal; the ground conductor being a sheet metal conductor is larger in plane dimension than the wireless circuit board; and the wireless terminal unit further comprises: a short terminal for connecting the wireless circuit board with the antenna element, one end of the short terminal being electrically connected with a ground of the wireless circuit board and the other end of the short terminal is electrically connected with the antenna element.