The present invention discloses:an IC inlet 110 which comprises a substrate 2, a surface circuit including a plain coil circuit portion 6 formed on the substrate and opposed electrodes 8 and 12 individually connected with the two ends of the plain coil circuit portion 6, and an IC chip 16 mounted in connection with the opposed electrodes, wherein a cut-away broken line 22 formed in at least a portion of the surface circuit so as to pass through the substrate and the surface circuit, and IC tag which is produced by the use of the IC inlet.