Heavy metal contamination of water resources is a critical issue which adversely affects humans. Ferrate(VI) (FeVIO42−, Fe(VI)), as a new type of green multifunctional water treatment agent, has shown promising potential for environmental decontamination. A complete understanding of the interactions between ferrate(VI) and toxic metals can be conducive to the further development of ferrate(VI) technology for application to wastewater treatment. This review first introduces the purification of ferrate(VI) technology for toxic metals including free heavy metals and metal complexes briefly. The effective parameters are then analyzed and discussed in detail. Subsequently, the reactivity and mechanisms of ferrate(VI) with toxic metals are emphatically described. Finally, possible research challenges and directions for ferrate(VI) technology applied to wastewater treatment in the future are summarized.