Compact dual-band dual-channel bandpass filters (BPFs) with different and identical frequency allocations are presented in this brief. Because of the magnetic boundary condition, four resonant modes are excited in the dielectric resonator (DR). The excitation and coupling scheme are analyzed and therefore dual-passband with different frequencies and bandwidths are obtained in each channel. Moreover, benefiting from the two pairs of orthogonal degenerate modes and excitation principle, the high isolation between the two channels is guaranteed. For verification, two dual-band dual-channel BPFs are designed. With only two DRs and two sets of probes, low insertion loss and high isolation better than 38 dB are achieved in the dual-band dual-channel BPF with the same passbands. It demonstrates that the proposed method would replace four conventional BPFs in the massive input massive output communication systems and the volume and number of resonators could be remarkably reduced.