An antenna coil includes a wound body including a magnetic core, a bobbin surrounding the magnetic core, and a coil wound around the bobbin, a case in which the wound body is placed, and a foam disposed in a gap between the wound body and the case. The foam is compressed at a rate of about 45% to about 65% on the basis of a thickness of the foam in a non-load state. The antenna coil prevents breakage of the magnetic core and is suitable for use in a short-distance communication system in an LF-band.