PURPOSE: To attain easily a desired frequency characteristic by constituting a dielectric filter with a columnar dielectric resonator and a prismatic dielectric resonator.

CONSTITUTION: The waveguide mode propagated in a standard waveguide part 1 is intercepted by an intercepting waveguide part 3 and is not propagated there. However, only waves resonating to arranged and fixed dielectric resonators 2 in the waveguide part 3 pass through the waveguide part 3. The columnar dielectric resonator is arranged in the center of the waveguide part 3, and prismatic dielectric resonators 2 are arranged in both ends, and individual resonators are fixed by dielectric substrates 7 having a low dielectric constant.