PURPOSE: To improve the resonance frequency versus temperature characteristics at a desired resonance frequency, by varying a distance between the surface of a lower ground conductor and a lower surface of a dielectric resonator and individually making the resonance frequency and thr resonance frequency versus temperature characteristics adjustable.

CONSTITUTION: A part of an upper ground conductor 6 is made of screw 7. The lower surface 8 of the screw 7 opposes to an upper surface 9 of a dielectric resonator 1. A distance S1 between the lower surface of the screw 7 and the upper surface 9 of the dielectric resonator 1 is changed by adjusting the screw 7. A part of a lower ground conductor 5 is taken as a screw 10. An upper part 11 of the screw 10 opposes to a lower surface 12 of the resonator 1 via a ceramic base 3. A distance S2 between the ceramic base 3 and the upper surface 11 of the screw 10 is changed by adjusting the screw 10. The distances S1 and S2 are changed by adjusting the screws 7 and 10, allowing to adjust both resonance frequency and the resonance frequency versus temperature characteristics.