The invention relates to a electric connection structure and an antenna apparatus. The antenna apparatus (1) has a base (3), a cover (4) on the base, a circuit board (5) vertically disposed on the base while accommodated in the cover;, a connection terminal (10) mounted on the circuit board, a support metalwork (45) disposed on the cover upon the circuit board and an antenna component (46) mounted on the support metalwork. The connection terminal (10) has a clamping unit (11) disposed along the upper end surface (51) of the circuit board, a retaining piece (12) connected with one end of the clamping unit, and a retaining piece (13) connected with the other end of the clamping unit while clamping the circuit board together with the retaining piece (12), a flat spring unit (14) connected with the retaining piece (13) while bent to the retaining piece (13) side on the connection part; wherein the support metalwork (45) is extruded to the direction to enlarge the interior angle composed by the retaining piece (13) and the flat spring unit (14).