Abstract: An ingeniously designed new dielectric filter is disclosed. Such a dielectric filter comprises a first pair of groove side wall electrodes arranged on a side wall of a groove in juxtaposition with a pair of patterned input/output electrodes formed on a substrate. Since such an arrangement can provide a relatively high input/output coupled capacity of a dielectric filter, such a dielectric filter can be realized without requiring preparation of complex and finely patterned electrodes and formation of patterned capacitor electrodes on a face of a dielectric block that constitutes a principal component of the dielectric filter. The frequency of such a dielectric filter can be adjusted by simply abrasing that face of the dielectric block.