Abstract: In this study, the issues of inductor current fluctuation and high common mode voltage (CMV) in Z-source ultra-sparse matrix converter (ZSUSMC) are investigated. Low voltage transfer ratio (VTR)(VTR ≤ 0.866) and high CMV are the main flaws of the conventional ultra-sparse matrix converter (USMC). However, the former drawback can be effectively fixed by inserting a cascaded Z-source network between the rectifier side and the inverter side and using a shoot-through (ST) vector during the switching cycle. The inductor in the Z-source network is charged by the capacitor in the ST state, and the inductor discharges to the capacitor in the non-shoot-through (NST) state. Therefore, the fluctuation of the inductor current can be reduced by placing the ST vector and the NST vector appropriately. The modulation strategy proposed in this paper divides the ST time into unequal six parts and inserts them alternately into the switching cycles to reduce the fluctuation of inductor current. In addition, to reduce the common-mode voltage in the ZSUSMC, this paper uses four active vectors at the inverter side instead of the conventional modulation with two active vectors and two zero vectors. Finally, the proposed modulation strategy is analyzed through software simulation and hardware experiments, and the results show that the modulation strategy can effectively reduce the inductor current fluctuation and peak of the CMV.