The present invention provides a small-sized filter which has good characteristics. A filter according to the present invention comprises: a resonator which has a via electrode part that is formed within a dielectric substrate and a first strip line that is connected to one end of the via electrode part, while facing a first shielding conductor among a plurality of shielding conductors that are formed so as to surround the via electrode part; an input/output terminal which is coupled to a second shielding conductor among the plurality of shielding conductors; and a first capacitor electrode pattern which is coupled to the input/output terminal. The first capacitor electrode pattern is capacitively coupled to the first strip line or a second capacitor electrode pattern that is connected to the via electrode part.