Antenna matching circuit, mobile communication device including antenna matching circuit, and dielectric antenna including antenna matching circuit

In an antenna matching circuit including a parallel resonant section (3) connected to a radiation element constituting an antenna (4), the parallel resonant section includes a series resonant portion composed of an inductance component (L1) and a capacitance component (C). The series resonant portion realizes antenna matching and band widening. The parallel resonant section can be inserted in a feeder line connected to the radiation element or inserted in a GND line connected to the radiation element. The matching circuit can be used in a dielectric antenna, which may be constructed from layered dielectric substrates.