The invention relates to a carrier PWM-based Z-source two-stage matrix converter modulation method. As for a rectification stage, an input phase voltage is divided into six sectors, two line voltagesof which the amplitudes are maximum and of which the polarities are positive are selected in each sector so as to be synthesized into an outputted direct-current voltage, and corresponding duty ratiosare calculated; as for an inversion stage, space voltage vector modulation is adopted, and the duty ratios of effective voltage vectors and zero voltage vectors are calculated according to a sector in which a reference voltage vector is located; and as for a Z-source network, straight-through voltage vectors are properly and reasonably inserted into the zero vectors of the inversion stage, and therefore, a voltage transmission ratio can be improved. The PWM signal diagram of power switches is drawn according to an entire modulation process; and the modulation signals of six sets of bidirectional power switches of the rectification stage and the modulation signals of six sets of power switches of the inversion stage are calculated and compared with the same triangular carrier signal, so that the driving signals of the bidirectional power switches of the rectification stage and the driving signals of the power switches of the inversion stage can be obtained. The method has the advantages of simplicity in calculation and easiness in implementation.