A multi-frequency antenna (1) comprises a dielectric substrate (100), an antenna element (110), a shunt inductor (120), a capacitor conductor (130), a series inductor (140), a grounded part (150) and a feeding point (160). The antenna element (110) is arranged on the substrate (100), and is electrically connected to the grounded part (150) through the shunt inductor (120). Moreover, the antenna element (110) is electrically connected to the feeding point (160) through a series capacitor formed by a part where the antenna element (110) faces the capacitor conductor (130) and the substrate (100) therebetween, and through the series inductor (140).