The effect of the addition of Bi2O3 on the densification,! low-temperature sintering, and electromagnetic properties of Z-type planar hexaferrite was investigated. The results show that Bi2O3 additives can improve the densification and promote low-temperature sintering of Z-type hexaferrite prepared by a solid-state reaction method. The presence of Bi2O3 in the grain boundaries and the generation of Fe2+ degrade the initial permeability of the samples but make the quality factor and cut-off frequency increase. Various possible mechanisms involved in generating these effects were also discussed.