A filter comprising: a substrate configured to perform a grounding operation; a resonator comprising: a body formed of a dielectric material wherein the body comprises two end surfaces parallel to each other and at least one side surface connecting the end surfaces, and wherein the body further includes a through-hole connecting the end surfaces in a lengthwise direction, wherein the resonator comprises a conductive film coupled to a wall surface of the through-hole and the two end surfaces of the body without being coupled to the at least one side surface of the body; the filter further comprising a housing coupled to the substrate to accommodate the resonator in a cavity thereof partitioned into a plurality of regions; wherein the housing comprises: a plurality of partitions configured to partition the cavity into a plurality of regions, wherein the cavity is perforated in a predetermined size; an input connector configured to receive a signal from the outside; an output connector configured to output a signal filtered through the resonator to the outside; an input coupling disk coupled to the input connector to transmit a signal received via the input connector to the resonator, and disposed apart by a predetermined distance from the resonator; and an output coupling disk configured to transmit a signal output from the resonator to the output connector, and disposed apart by a predetermined distance from the resonator. a substrate configured to perform a grounding operation; a resonator comprising: a body formed of a dielectric material wherein the body comprises two end surfaces parallel to each other and at least one side surface connecting the end surfaces, and wherein the body further includes a through-hole connecting the end surfaces in a lengthwise direction, wherein the resonator comprises a conductive film coupled to a wall surface of the through-hole and the two end surfaces of the body without being coupled to the at least one side surface of the body; the filter further comprising a housing coupled to the substrate to accommodate the resonator in a cavity thereof partitioned into a plurality of regions; wherein the housing comprises: a plurality of partitions configured to partition the cavity into a plurality of regions, wherein the cavity is perforated in a predetermined size; an input connector configured to receive a signal from the outside; an output connector configured to output a signal filtered through the resonator to the outside; an input coupling disk coupled to the input connector to transmit a signal received via the input connector to the resonator, and disposed apart by a predetermined distance from the resonator; and an output coupling disk configured to transmit a signal output from the resonator to the output connector, and disposed apart by a predetermined distance from the resonator. a body formed of a dielectric material wherein the body comprises two end surfaces parallel to each other and at least one side surface connecting the end surfaces, and wherein the body further includes a through-hole connecting the end surfaces in a lengthwise direction, wherein the resonator comprises a conductive film coupled to a wall surface of the through-hole and the two end surfaces of the body without being coupled to the at least one side surface of the body; the filter further comprising a housing coupled to the substrate to accommodate the resonator in a cavity thereof partitioned into a plurality of regions; wherein the housing comprises: a plurality of partitions configured to partition the cavity into a plurality of regions, wherein the cavity is perforated in a predetermined size; an input connector configured to receive a signal from the outside; an output connector configured to output a signal filtered through the resonator to the outside; an input coupling disk coupled to the input connector to transmit a signal received via the input connector to the resonator, and disposed apart by a predetermined distance from the resonator; and an output coupling disk configured to transmit a signal output from the resonator to the output connector, and disposed apart by a predetermined distance from the resonator. a plurality of partitions configured to partition the cavity into a plurality of regions, wherein the cavity is perforated in a predetermined size; an input connector configured to receive a signal from the outside; an output connector configured to output a signal filtered through the resonator to the outside; an input coupling disk coupled to the input connector to transmit a signal received via the input connector to the resonator, and disposed apart by a predetermined distance from the resonator; and an output coupling disk configured to transmit a signal output from the resonator to the output connector, and disposed apart by a predetermined distance from the resonator.