PURPOSE: To provide an antenna by which radiation efficiency is improved and whose directivity is satisfactory by providing a feeding electrode hole which is parallel to a radiation electrode and in which a feeding electrode is provided at an inner wall on one side where a ground electrode is not formed.

CONSTITUTION: The radiation electrode 2 is formed in the center of a dielectric substrate 1 consisting of a rectangular parallelopiped or a cube and the ground electrode 3 which is insulated from the radiation electrode 2 and which is continuous from the upper surface of the dielectric substrate 1 to one opposing side or a lower surface is formed. The radiation electrode 2 and the ground electrode 3 are constituted by silver and the like. The feeding electrode hole 1a parallel to the radiation electrode 2 is formed in the center of one side where the ground electrode 3 of the dielectric substrate 1 is not formed, and the feeding electrode 4 consisting of silver, for example, is formed at the inner wall of the feeding electrode hole 1a so that the end part is exposed to the side so as to constitute the antenna 5. The radiation electrode 2 and the feeding electrode 4 are electromagnetically connected, and the ground electrode 3 and the feeding electrode 4 form a coaxial line.