To meet the development requirements of the filters in the dualband communication system, a novel dual bandpass filter design method based on the quartermode substrate integrated waveguide (QMSIW) loaded complementary split ring resonator (CSRR) is proposed. Based on the transmission characteristics of the CSRR resonator, the first passband centered on its resonant frequency can be realized; the side length of the QMSIW resonator is designed to realize the second passband centered on the resonant frequency of the cavity. The coupling mode between QMSIW cavities is designed and a transmission zero points between the two passbands and at the high stopband are introduced respectively to enhance the isolation and outofband rejection of the two passbands. The center frequencies of a two passbands are designed to be 8.1 GHz and 11.5 GHz, respectively, and the effective size is only 15 mm×8 mm, its insertionloss is less than 0.4 dB, the high stopband attenuation is 64 dB, and the isolation between the two passbands is 46 dB.