In this paper, a new coupled resonator which expands free spectral ranges (FSR) of the W. G. mode resonators is presented. The proposed coupled resonator consists of two dielectric disks. The resonance frequency of the coupled resonator is equivalent to the frequency, which satisfies the individual resonance conditions of each disk at the same time. As the results, the FSR is expanded. The coupled resonator proposed in this paper at K-Band is fabricated by using dielectric disks and the dielectric straight waveguides. The validity of proposed coupled resonator was verified through experiments.