An antenna circuit includes a radiation conductor, a matching circuit disposed between a feeding port in the radiation conductor and a feeder circuit, and a frequency-characteristics adjusting circuit connected between a frequency-characteristics adjustment port in the radiation conductor and a ground and including a variable reactance circuit. The matching circuit includes a first inductance element connected in shunt. The frequency-characteristics adjusting circuit includes a second inductance element. The first inductance element and the second inductance element are magnetically coupled to each other.