Two new vector modes of one-cycle control three-level APF are presented in this paper.The topology of three-level four-leg inverter was studied,and the mathematical model was analyzed.Considering that the DC capacitor voltage can balance automatically,with the help of absolute switching state table two new vector modes of one-cycle control three-level APF were proposed,and the control objective equations were derived.The simulation shows that these modes are able to compensate the harmonic current effectively and reduce switching losses and neutral current,which verifies their validity and feasibility.