A nonradiative dielectric waveguide filter of the present invention permits the manufacturing process including the production of a dielectric strip to be simpler. The filter can be formed by a pillar dielectric strip. The nonradiative dielectric waveguide filter includes resonators, input-output connection units, and cut-off regions, in which the upper and lower conductor plates and a dielectric strip disposed therebetween form the filter. In one example, the main signal-transmitting mode is the LSM mode; a groove having a bottom and conductor walls is disposed in a position in which the conductor plates are opposing; the resonator is formed by fitting the dielectric strip into the groove; and the cut-off regions are formed by second grooves formed in the conductor plates adjacent to the dielectric strip.