PURPOSE: To reduce the man-hour for production considerably and to obtain a mechanically stable shared block by constituting plural filter parts on a single dielectric block and coupling filter parts by the second resonance element.

CONSTITUTION: A pair of filter parts 102a and 102b are formed as one body on a single dielectric block 101. The second through hole 110 is formed in parallel with the first through holes 103 in the middle between the first resonance elements 105 placed in opposite end parts of both filter parts 102a and 102b. This through hole 110 is formed to have a diameter smaller than that of through holes 103, and a connecting electrode 111 is formed on its inside peripheral surface. The second resonance element 112 is constituted with this connecting electrode 111, an outer conductor 106, and a dielectric block 101. Magnetic field coupling is caused between filter parts 102a and 102b and they are coupled by the electric field generated among the connecting electrode 111 of the resonance element 112, inner conductors 104 of resonance elements 105 on both sides, and the outer conductor 106, thus constituting a shared dielectric block.